©2004 by Marc J. Rochkind. All rights reserved. Portions marked "Open Source" may be copied under license.

 

                 

---

SUS_Summary

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/* Do not modify this file -- it was generated automatically. */
/**
\par Description:
Clear fd_set bit
(Std. UNIX; see AUP2 Sec. 4.2.3)
\par Headers:
    sys/select.h
*/
void FD_CLR(
int fd, /**< file descriptor to clear*/
fd_set *fdset   /**< fd_set*/
);
/**
\par Description:
Test fd_set bit
(Std. UNIX; see AUP2 Sec. 4.2.3)
\par Headers:
    sys/select.h
\return 1 if set or 0 if clear (no error return)
*/
int FD_ISSET(
int fd, /**< file descriptor to test*/
fd_set *fdset   /**< fd_set*/
);
/**
\par Description:
Set fd_set bit
(Std. UNIX; see AUP2 Sec. 4.2.3)
\par Headers:
    sys/select.h
*/
void FD_SET(
int fd, /**< file descriptor to set*/
fd_set *fdset   /**< fd_set*/
);
/**
\par Description:
Clear entire fd_set
(Std. UNIX; see AUP2 Sec. 4.2.3)
\par Headers:
    sys/select.h
*/
void FD_ZERO(
fd_set *fdset   /**< fd_set to clear*/
);
/**
\par Description:
Terminate process without clean-up
(Std. UNIX; see AUP2 Sec. 5.7)
\par Headers:
    stdlib.h
\return Does not return
*/
void _Exit(
int status  /**< exit status*/
);
/**
\par Description:
Terminate process without clean-up
(Std. UNIX; see AUP2 Sec. 5.7)
\par Headers:
    unistd.h
\return Does not return
*/
void _exit(
int status  /**< exit status*/
);
/**
\par Description:
Jump to jump point without restoring signal mask
(Std. UNIX; see AUP2 Sec. 9.6)
\par Headers:
    setjmp.h
*/
void _longjmp(
jmp_buf loc_info,   /**< saved location information*/
int val /**< value for setjmp to return*/
);
/**
\par Description:
Set jump point
(Std. UNIX; see AUP2 Sec. 9.6)
\par Headers:
    setjmp.h
\return 0 if called directly, non-zero if from longjmp (no error return)
*/
int _setjmp(
jmp_buf loc_info    /**< saved location information*/
);
/**
\par Description:
Generate SIGABRT
(Std. UNIX; see AUP2 Sec. 9.1.9)
\par Headers:
    stdlib.h
\return Does not return
*/
void abort(void);
/**
\par Description:
Accept new connection on socket and create new socket
(Std. UNIX; see AUP2 Sec. 8.1.2)
\par Headers:
    sys/socket.h
\return file descriptor or -1 on error (sets errno)
*/
int accept(
int socket_fd,  /**< socket file descriptor*/
struct sockaddr *sa,    /**< socket address or NULL*/
socklen_t *sa_len   /**< address length*/
);
/**
\par Description:
Determine accessibility of file
(Std. UNIX; see AUP2 Sec. 3.8.1)
<p>R_OK     read permission 
<br>W_OK        write permission 
<br>X_OK        execute (search) permission 
<br>F_OK        test for existence 
\par Headers:
    unistd.h
\return 0 if allowed or -1 if not or on error (sets errno)
*/
int access(
const char *path,   /**< pathname*/
int what    /**< permission to be tested*/
);
/**
\par Description:
Cancel asynchronous I/O request
(Std. UNIX; see AUP2 Sec. 3.9.5)
\par Headers:
    aio.h
\return result code or -1 on error (sets errno)
*/
int aio_cancel(
int fd, /**< file descriptor*/
struct aiocb *aiocbp    /**< control block*/
);
/**
\par Description:
Retrieve error status for asynchronous I/O operation
(Std. UNIX; see AUP2 Sec. 3.9.4)
\par Headers:
    aio.h
\return 0, errno value, or EINPROGRESS (does not set errno)
*/
int aio_error(
const struct aiocb *aiocbp  /**< control block*/
);
/**
\par Description:
Initiate buffer-cache flushing for one file
(Std. UNIX; see AUP2 Sec. 3.9.6)
\par Headers:
    aio.h
\return 0 on success or -1 on error (sets errno)
*/
int aio_fsync(
int op, /**< O_SYNC or O_DSYNC*/
struct aiocb *aiocbp    /**< control block*/
);
/**
\par Description:
Asynchronous read from file
(Std. UNIX; see AUP2 Sec. 3.9.3)
\par Headers:
    aio.h
\return 0 on success or -1 on error (sets errno)
*/
int aio_read(
struct aiocb *aiocbp    /**< control block*/
);
/**
\par Description:
Retrieve return status of asynchronous I/O operation
(Std. UNIX; see AUP2 Sec. 3.9.4)
\par Headers:
    aio.h
\return operation return value or -1 on error (sets errno)
*/
ssize_t aio_return(
struct aiocb *aiocbp    /**< control block*/
);
/**
\par Description:
Wait for asynchronous I/O request
(Std. UNIX; see AUP2 Sec. 3.9.7)
\par Headers:
    aio.h
\return 0 on success or -1 on error (sets errno)
*/
int aio_suspend(
const struct aiocb *const list[],   /**< array of control blocks*/
int cbcnt,  /**< number of elements in array*/
const struct timespec *timeout  /**< max time to wait*/
);
/**
\par Description:
Asynchronous write to file
(Std. UNIX; see AUP2 Sec. 3.9.3)
\par Headers:
    aio.h
\return 0 on success or -1 on error (sets errno)
*/
int aio_write(
struct aiocb *aiocbp    /**< control block*/
);
/**
\par Description:
Schedule an alarm signal
(Std. UNIX; see AUP2 Sec. 9.7.1)
\par Headers:
    unistd.h
\return seconds left on previous alarm or zero if none (no error return)
*/
unsigned alarm(
unsigned secs   /**< seconds until signal*/
);
/**
\par Description:
Convert broken-down time to local-time string
(Std. UNIX; see AUP2 Sec. 1.7.1)
\par Headers:
    time.h
\return string or NULL on error (errno not set)
*/
char *asctime(
const struct tm * tmbuf /**< broken-down time*/
);
/**
\par Description:
Register function to be called when process exits
(Std. UNIX; see AUP2 Sec. 1.3.4)
\par Headers:
    stdlib.h
\return 0 on success, non-zero on error (errno not set)
*/
int atexit(
void (*fcn)(void)   /**< function to be called*/
);
/**
\par Description:
Bind name to socket
(Std. UNIX; see AUP2 Sec. 8.1.2)
\par Headers:
    sys/socket.h
\return 0 on success or -1 on error (sets errno)
*/
int bind(
int socket_fd,  /**< socket file descriptor*/
const struct sockaddr *sa,  /**< socket address*/
socklen_t sa_len    /**< address length*/
);
/**
\par Description:
Get input speed from termios structure
(Std. UNIX; see AUP2 Sec. 4.5.3)
\par Headers:
    termios.h
\return speed (no error return)
*/
speed_t cfgetispeed(
const struct termios *tp    /**< attributes*/
);
/**
\par Description:
Get output speed from termios structure
(Std. UNIX; see AUP2 Sec. 4.5.3)
\par Headers:
    termios.h
\return speed (no error return)
*/
speed_t cfgetospeed(
const struct termios *tp    /**< attributes*/
);
/**
\par Description:
Set input speed in termios structure
(Std. UNIX; see AUP2 Sec. 4.5.3)
\par Headers:
    termios.h
\return 0 on success or -1 on error (may set errno)
*/
int cfsetispeed(
struct termios *tp, /**< attributes*/
speed_t speed   /**< speed*/
);
/**
\par Description:
Set output speed in termios structure
(Std. UNIX; see AUP2 Sec. 4.5.3)
\par Headers:
    termios.h
\return 0 on success or -1 on error (may set errno)
*/
int cfsetospeed(
struct termios *tp, /**< attributes*/
speed_t speed   /**< speed*/
);
/**
\par Description:
Change current directory by path
(Std. UNIX; see AUP2 Sec. 3.6.2)
\par Headers:
    unistd.h
\return 0 on success or -1 on error (sets errno)
*/
int chdir(
const char *path    /**< pathname*/
);
/**
\par Description:
Change mode of file by path
(Std. UNIX; see AUP2 Sec. 3.7.1)
\par Headers:
    sys/stat.h
\return 0 on success or -1 on error (sets errno)
*/
int chmod(
const char *path,   /**< pathname*/
mode_t mode /**< new mode*/
);
/**
\par Description:
Change owner and group of file by path
(Std. UNIX; see AUP2 Sec. 3.7.2)
\par Headers:
    unistd.h
\return 0 on success or -1 on error (sets errno)
*/
int chown(
const char *path,   /**< pathname*/
uid_t uid,  /**< new user ID*/
gid_t gid   /**< new group ID*/
);
/**
\par Description:
Change root directory
(Std. UNIX; see AUP2 Sec. 5.14)
\par Headers:
    unistd.h
\return 0 on success or -1 on error (sets errno)
*/
int chroot(
const char *path    /**< path name*/
);
/**
\par Description:
Get execution time
(Std. UNIX; see AUP2 Sec. 1.7.2)
\par Headers:
    time.h
\return time in CLOCKS_PER_SEC or -1 on error (errno not set)
*/
clock_t clock(void);
/**
\par Description:
Get process CPU-time clock
(Std. UNIX; see AUP2 Sec. 9.7.5)
\par Headers:
    time.h
\return 0 on success or error number on error
*/
int clock_getcpuclockid(
pid_t pid,  /**< process ID*/
clockid_t *clock_id /**< returned clock ID*/
);
/**
\par Description:
Get clock resolution
(Std. UNIX; see AUP2 Sec. 9.7.5)
\par Headers:
    time.h
\return 0 on success or -1 on error (sets errno)
*/
int clock_getres(
clockid_t clock_id, /**< clock ID*/
struct timespec *res    /**< resolution*/
);
/**
\par Description:
Get time from clock
(Std. UNIX; see AUP2 Sec. 9.7.5)
\par Headers:
    time.h
\return 0 on success or -1 on error (sets errno)
*/
int clock_gettime(
clockid_t clock_id, /**< clock ID (CLOCK_REALTIME, etc.)*/
struct timespec *tp /**< time*/
);
/**
\par Description:
Suspend execution for nanoseconds or until signal
(Std. UNIX; see AUP2 Sec. 9.7.5)
\par Headers:
    time.h
\return 0 on success or error number on error
*/
int clock_nanosleep(
clockid_t clock_id, /**< clock ID*/
int flags,  /**< TIMER_ABSTIME or zero*/
const struct timespec *nsecs,   /**< nanoseconds to sleep*/
struct timespec *remain /**< remaining time*/
);
/**
\par Description:
Set clock
(Std. UNIX; see AUP2 Sec. 9.7.5)
\par Headers:
    time.h
\return 0 on success or -1 on error (sets errno)
*/
int clock_settime(
clockid_t clock_id, /**< clock ID*/
const struct timespec *tp   /**< time*/
);
/**
\par Description:
Close file descriptor
(Std. UNIX; see AUP2 Sec. 2.11)
\par Headers:
    unistd.h
\return 0 on success or -1 on error (sets errno)
*/
int close(
int fd  /**< file descriptor*/
);
/**
\par Description:
Close directory
(Std. UNIX; see AUP2 Sec. 3.6.1)
\par Headers:
    dirent.h
\return 0 on success or -1 on error (sets errno)
*/
int closedir(
DIR *dirp   /**< DIR pointer from opendir*/
);
/**
\par Description:
Get configuration string
(Std. UNIX; see AUP2 Sec. 1.5.7)
\par Headers:
    unistd.h
\return size of value or 0 on error (sets errno on error)
*/
size_t confstr(
int name,   /**< option or limit name*/
char *buf,  /**< returned string value*/
size_t len  /**< size of buf*/
);
/**
\par Description:
Connect socket
(Std. UNIX; see AUP2 Sec. 8.1.2)
\par Headers:
    sys/socket.h
\return 0 on success or -1 on error (sets errno)
*/
int connect(
int socket_fd,  /**< socket file descriptor*/
const struct sockaddr *sa,  /**< socket address*/
socklen_t sa_len    /**< address length*/
);
/**
\par Description:
Create or truncate a file for writing
(Std. UNIX; see AUP2 Sec. 2.4.2)
\par Headers:
    sys/stat.h
    , fcntl.h
\return file descriptor  or -1 on error (sets errno)
*/
int creat(
const char *path,   /**< pathname*/
mode_t perms    /**< permissions*/
);
/**
\par Description:
Get pathname for controlling terminal
(Std. UNIX; see AUP2 Sec. 4.7)
\par Headers:
    stdio.h
\return pathname or empty string on error (errno not set)
*/
char *ctermid(
char *buf   /**< buffer of size L_ctermid or NULL*/
);
/**
\par Description:
Convert time_t to local-time string
(Std. UNIX; see AUP2 Sec. 1.7.1)
\par Headers:
    time.h
\return string or NULL on error (errno not set)
*/
char *ctime(
const time_t *t /**< time*/
);
/**
\par Description:
Subtract two time_t values
(Std. UNIX; see AUP2 Sec. 1.7.1)
\par Headers:
    time.h
\return time1 - time0 in seconds (no error return)
*/
double difftime(
time_t time1,   /**< time*/
time_t time0    /**< time*/
);
/**
\par Description:
Duplicate file descriptor
(Std. UNIX; see AUP2 Sec. 6.3)
\par Headers:
    unistd.h
\return new file descriptor or -1 on error (sets errno)
*/
int dup(
int fd  /**< file descriptor to duplicate*/
);
/**
\par Description:
Duplicate file descriptor
(Std. UNIX; see AUP2 Sec. 6.3)
\par Headers:
    unistd.h
\return new file descriptor or -1 on error (sets errno)
*/
int dup2(
int fd, /**< file descriptor to duplicate*/
int fd2 /**< file descriptor to use*/
);
/**
\par Description:
End host-database scan
(Std. UNIX; see AUP2 Sec. 8.8.1)
\par Headers:
    netdb.h
*/
void endhostent(void);
/**
\par Description:
End network-database scan
(Std. UNIX; see AUP2 Sec. 8.8.2)
\par Headers:
    netdb.h
*/
void endnetent(void);
/**
\par Description:
End protocol-database scan
(Std. UNIX; see AUP2 Sec. 8.8.3)
\par Headers:
    netdb.h
*/
void endprotoent(void);
/**
\par Description:
End service-database scan
(Std. UNIX; see AUP2 Sec. 8.8.4)
\par Headers:
    netdb.h
*/
void endservent(void);
/**
\par Description:
Execute file with argument list
(Std. UNIX; see AUP2 Sec. 5.3)
\par Headers:
    unistd.h
\return -1 on error (sets errno)
*/
int execl(
const char *path,   /**< program pathname*/
const char *arg0,   /**< first arg (file name)*/
const char *arg1,   /**< second arg*/
...,    /**< remaining args*/
NULL    /**< arg list terminator*/
);
/**
\par Description:
Execute file with argument list and environment
(Std. UNIX; see AUP2 Sec. 5.3)
\par Headers:
    unistd.h
\return -1 on error (sets errno)
*/
int execle(
const char *path,   /**< program pathname*/
const char *arg0,   /**< first arg (file name)*/
const char *arg1,   /**< second arg*/
...,    /**< remaining args*/
NULL    /**< arg list terminator*/
char *const envv[]*/    /**< environment vector*/
);
/**
\par Description:
Execute file with argument list and PATH search
(Std. UNIX; see AUP2 Sec. 5.3)
\par Headers:
    unistd.h
\return -1 on error (sets errno)
*/
int execlp(
const char *file,   /**< program file name*/
const char *arg0,   /**< first arg (file name)*/
const char *arg1,   /**< second arg*/
...,    /**< remaining args*/
NULL    /**< arg list terminator*/
);
/**
\par Description:
Execute file with argument vector
(Std. UNIX; see AUP2 Sec. 5.3)
\par Headers:
    unistd.h
\return -1 on error (sets errno)
*/
int execv(
const char *path,   /**< program pathname*/
char *const argv[]  /**< argument vector*/
);
/**
\par Description:
Execute file with argument vector and environment
(Std. UNIX; see AUP2 Sec. 5.3)
\par Headers:
    unistd.h
\return -1 on error (sets errno)
*/
int execve(
const char *path,   /**< program pathname*/
char *const argv[], /**< argument vector*/
char *const envv[]  /**< environment vector*/
);
/**
\par Description:
Execute file with argument vector and PATH search
(Std. UNIX; see AUP2 Sec. 5.3)
\par Headers:
    unistd.h
\return -1 on error (sets errno)
*/
int execvp(
const char *file,   /**< program file name*/
char *const argv[]  /**< argument vector*/
);
/**
\par Description:
Terminate process with clean-up
(Std. UNIX; see AUP2 Sec. 5.7)
\par Headers:
    stdlib.h
\return Does not return
*/
void exit(
int status  /**< exit status*/
);
/**
\par Description:
Change current directory by file descriptor
(Std. UNIX; see AUP2 Sec. 3.6.2)
\par Headers:
    unistd.h
\return 0 on success or -1 on error (sets errno)
*/
int fchdir(
int fd  /**< file descriptor*/
);
/**
\par Description:
Change mode of file by file descriptor
(Std. UNIX; see AUP2 Sec. 3.7.1)
\par Headers:
    sys/stat.h
\return 0 on success or -1 on error (sets errno)
*/
int fchmod(
int fd, /**< file descriptor*/
mode_t mode /**< new mode*/
);
/**
\par Description:
Change owner and group of file by file descriptor
(Std. UNIX; see AUP2 Sec. 3.7.2)
\par Headers:
    unistd.h
\return 0 on success or -1 on error (sets errno)
*/
int fchown(
int fd, /**< file descriptor*/
uid_t uid,  /**< new user ID*/
gid_t gid   /**< new group ID*/
);
/**
\par Description:
Control open file
(Std. UNIX; see AUP2 Sec. 3.8.3)
\par Headers:
    unistd.h
    , fcntl.h
\return result depending on op or -1 on error (sets errno)
*/
int fcntl(
int fd, /**< file descriptor*/
int op, /**< operation*/
... /**< optional argument depending on op*/
);
/**
\par Description:
Force buffer-cache flushing for one file’s data
(Std. UNIX; see AUP2 Sec. 2.16.2)
\par Headers:
    unistd.h
\return 0 or -1 on error (sets errno)
*/
int fdatasync(
int fd  /**< file descriptor*/
);
/**
\par Description:
Create new process
(Std. UNIX; see AUP2 Sec. 5.5)
\par Headers:
    unistd.h
\return child’s process-ID and 0 on success or -1 on error (sets errno)
*/
pid_t fork(void);
/**
\par Description:
Get system option or limit by file descriptor
(Std. UNIX; see AUP2 Sec. 1.5.6)
\par Headers:
    unistd.h
\return option/limit value or -1 (sets errno on error)
*/
long fpathconf(
int fd, /**< file descriptor*/
int name    /**< option or limit name*/
);
/**
\par Description:
Free socket-address information
(Std. UNIX; see AUP2 Sec. 8.2.6)
\par Headers:
    sys/socket.h
    , netdb.h
*/
void freeaddrinfo(
struct addrinfo *infop      /**< list to free*/
);
/**
\par Description:
Get file info by file descriptor
(Std. UNIX; see AUP2 Sec. 3.5.1)
\par Headers:
    sys/stat.h
\return 0 on success or -1 on error (sets errno)
*/
int fstat(
int fd, /**< file descriptor*/
struct stat *buf    /**< returned information*/
);
/**
\par Description:
Get file system information by file descriptor
(Std. UNIX; see AUP2 Sec. 3.2.3)
\par Headers:
    sys/statvfs.h
\return 0 on success or -1 on error (sets errno)
*/
int fstatvfs(
int fd, /**< file descriptor*/
struct statvfs *buf /**< returned info*/
);
/**
\par Description:
Schedule or force buffer-cache flushing for one file
(Std. UNIX; see AUP2 Sec. 2.16.2)
\par Headers:
    unistd.h
\return 0 on success or -1 on error (sets errno)
*/
int fsync(
int fd  /**< file descriptor*/
);
/**
\par Description:
Generate System V IPC key
(Std. UNIX; see AUP2 Sec. 7.4.2)
\par Headers:
    sys/ipc.h
\return key on success or -1 on error (sets errno)
*/
key_t ftok(
const char *path,   /**< pathname of existing file*/
int id  /**< desired key number*/
);
/**
\par Description:
Truncate or stretch file by file descriptor
(Std. UNIX; see AUP2 Sec. 2.17)
\par Headers:
    unistd.h
\return 0 on success or -1 on error (sets errno)
*/
int ftruncate(
int fd, /**< file descriptor*/
off_t length    /**< new length*/
);
/**
\par Description:
Get error-code description
(Std. UNIX; see AUP2 Sec. 8.2.6)
\par Headers:
    netdb.h
\return string (no error return)
*/
const char *gai_strerror(
int code    /**< error code*/
);
/**
\par Description:
Get socket-address information
(Std. UNIX; see AUP2 Sec. 8.2.6)
\par Headers:
    sys/socket.h
    , netdb.h
\return 0 on success or error number on error (errno not set)
*/
int getaddrinfo(
const char *nodename,   /**< node name*/
const char *servname,   /**< service name*/
const struct addrinfo *hint,    /**< hint*/
struct addrinfo **infop /**< returned info as linked list*/
);
/**
\par Description:
Get current directory pathname
(Std. UNIX; see AUP2 Sec. 3.4.2)
\par Headers:
    unistd.h
\return pathname or NULL on error (sets errno)
*/
char *getcwd(
char *buf,  /**< returned pathname*/
size_t bufsize  /**< size of buf*/
);
/**
\par Description:
Convert string to broken-down time with rules
(Std. UNIX; see AUP2 Sec. 1.7.1)
\par Headers:
    time.h
\return broken-down time or NULL on error (sets getdate_err)
*/
struct tm *getdate(
const char *s   /**< string to convert*/
);
/**
\par Description:
Get effective group ID
(Std. UNIX; see AUP2 Sec. 5.11)
\par Headers:
    unistd.h
\return group ID (no error return)
*/
gid_t getegid(void);
/**
\par Description:
Get value of environment variable
(Std. UNIX; see AUP2 Sec. 5.2)
\par Headers:
    stdlib.h
\return value or NULL if not found (errno not set)
*/
char *getenv(
const char *var /**< variable to find*/
);
/**
\par Description:
Get effective user ID
(Std. UNIX; see AUP2 Sec. 5.11)
\par Headers:
    unistd.h
\return user ID (no error return)
*/
uid_t geteuid(void);
/**
\par Description:
Get real group ID
(Std. UNIX; see AUP2 Sec. 5.11)
\par Headers:
    unistd.h
\return group ID (no error return)
*/
gid_t getgid(void);
/**
\par Description:
Get group-file entry
(Std. UNIX; see AUP2 Sec. 3.5.2)
\par Headers:
    grp.h
\return pointer to structure or NULL on error (sets errno)
*/
struct group *getgrgid(
gid_t gid   /**< group ID*/
);
/**
\par Description:
Lookup host by address
(Std. UNIX; see AUP2 Sec. 8.8.1)
\par Headers:
    netdb.h
\return pointer to hostent or NULL on error (sets h_errno)
*/
struct hostent *gethostbyaddr(
const void *addr,   /**< IP address*/
socklen_t len,  /**< length of address*/
int family  /**< family (called “type” in SUS)*/
);
/**
\par Description:
Lookup host by name
(Std. UNIX; see AUP2 Sec. 8.8.1)
\par Headers:
    netdb.h
\return pointer to hostent or NULL on error (sets h_errno)
*/
struct hostent *gethostbyname(
const char *nodename,   /**< node name*/
);
/**
\par Description:
Get next host-database entry
(Std. UNIX; see AUP2 Sec. 8.8.1)
\par Headers:
    netdb.h
\return next entry or NULL on end of database (errno not set)
*/
struct hostent *gethostent(void);
/**
\par Description:
Get identifier for local host
(Std. UNIX; see AUP2 Sec. 8.8.1)
\par Headers:
    unistd.h
\return identifier (no error return)
*/
long gethostid(void);
/**
\par Description:
Get name of host
(Std. UNIX; see AUP2 Sec. 8.2.7)
\par Headers:
    unistd.h
\return 0 on success or -1 on error (errno not set)
*/
int gethostname(
char *name, /**< returned name*/
size_t namelen  /**< size of name buffer*/
);
/**
\par Description:
Get value of interval timer
(Std. UNIX; see AUP2 Sec. 9.7.4)
\par Headers:
    sys/time.h
\return 0 on success or -1 on error (sets errno)
*/
int getitimer(
int which,  /**< timer to get*/
struct itimerval *val   /**< returned value*/
);
/**
\par Description:
Get login name
(Std. UNIX; see AUP2 Sec. 3.5.2)
\par Headers:
    unistd.h
\return name or NULL on error (sets errno)
*/
char *getlogin(void);
/**
\par Description:
Get name information
(Std. UNIX; see AUP2 Sec. 8.8.1)
\par Headers:
    sys/socket.h
    , netdb.h
\return 0 on success or error number on error
*/
int getnameinfo(
const struct sockaddr *sa,  /**< socket address*/
socklen_t sa_len,   /**< socket-address length*/
char *nodename, /**< node name*/
socklen_t nodelen,  /**< node-name buffer length*/
char *servname, /**< service name*/
socklen_t servlen,  /**< service-name buffer length*/
unsigned flags  /**< flags*/
);
/**
\par Description:
Lookup network by number
(Std. UNIX; see AUP2 Sec. 8.8.2)
\par Headers:
    netdb.h
\return pointer to netent or NULL if not found (errno not set)
*/
struct netent *getnetbyaddr(
uint32_t net,   /**< network number (to match n_net member)*/
int type    /**< family (to match n_addrtype member)*/
);
/**
\par Description:
Lookup network by name
(Std. UNIX; see AUP2 Sec. 8.8.2)
\par Headers:
    netdb.h
\return pointer to netent or NULL if not found (errno not set)
*/
struct netent *getnetbyname(
const char *name    /**< network name (to match n_name member)*/
);
/**
\par Description:
Get network-database entry
(Std. UNIX; see AUP2 Sec. 8.8.2)
\par Headers:
    netdb.h
\return pointer to netent or NULL end of database (errno not set)
*/
struct netent *getnetent(void);
/**
\par Description:
Get socket address of connected socket
(Std. UNIX; see AUP2 Sec. 8.9.2)
\par Headers:
    sys/socket.h
\return 0 on success or -1 on error (sets errno)
*/
int getpeername(
int socket_fd,  /**< socket file descriptor*/
struct sockaddr *sa,    /**< socket address*/
socklen_t *sa_len   /**< address length*/
);
/**
\par Description:
Get process-group ID
(Std. UNIX; see AUP2 Sec. 4.3.3)
\par Headers:
    unistd.h
\return process-group ID or -1 on error (sets errno)
*/
pid_t getpgid(
pid_t pid   /**< process ID or 0 for calling process*/
);
/**
\par Description:
Get process ID
(Std. UNIX; see AUP2 Sec. 5.13)
\par Headers:
    unistd.h
\return process ID (no error return)
*/
pid_t getpid(void);
/**
\par Description:
Get parent process ID
(Std. UNIX; see AUP2 Sec. 5.13)
\par Headers:
    unistd.h
\return parent process ID (no error return)
*/
pid_t getppid(void);
/**
\par Description:
Lookup protocol by name
(Std. UNIX; see AUP2 Sec. 8.8.3)
\par Headers:
    netdb.h
\return pointer to protoent or NULL if not found (errno not set)
*/
struct protoent *getprotobyname(
const char *name    /**< protocol name*/
);
/**
\par Description:
Lookup protocol by number
(Std. UNIX; see AUP2 Sec. 8.8.3)
\par Headers:
    netdb.h
\return pointer to protoent or NULL if not found (errno not set)
*/
struct protoent *getprotobynumber(
int proto   /**< protocol number*/
);
/**
\par Description:
Get protocol-database entry
(Std. UNIX; see AUP2 Sec. 8.8.3)
\par Headers:
    netdb.h
\return pointer to protoent or NULL end of database (errno not set)
*/
struct protoent *getprotoent(void);
/**
\par Description:
Get password-file entry
(Std. UNIX; see AUP2 Sec. 3.5.2)
\par Headers:
    pwd.h
\return pointer to structure or NULL on error (sets errno)
*/
struct passwd *getpwuid(
uid_t uid   /**< user ID*/
);
/**
\par Description:
Get resource limits
(Std. UNIX; see AUP2 Sec. 5.16)
\par Headers:
    sys/resource.h
\return 0 on success or -1 on error (sets errno)
*/
int getrlimit(
int resource,   /**< resource*/
struct rlimit *rlp  /**< returned limits*/
);
/**
\par Description:
Get resource usage
(Std. UNIX; see AUP2 Sec. 5.16)
\par Headers:
    sys/resource.h
\return 0 on success or -1 on error (sets errno)
*/
int getrusage(
int who,    /**< RUSAGE_SELF or RUSAGE_CHILDREN*/
struct rusage *r_usage  /**< returned usage information*/
);
/**
\par Description:
Lookup service by name
(Std. UNIX; see AUP2 Sec. 8.8.4)
\par Headers:
    netdb.h
\return pointer to protoent or NULL if not found (errno not set)
*/
struct servent *getservbyname(
const char *name,   /**< */
const char *proto   /**< */
);
/**
\par Description:
Lookup service by port
(Std. UNIX; see AUP2 Sec. 8.8.4)
\par Headers:
    netdb.h
\return pointer to protoent or NULL if not found (errno not set)
*/
struct servent *getservbyport(
int port,   /**< */
const char *proto   /**< */
);
/**
\par Description:
Get service-database entry
(Std. UNIX; see AUP2 Sec. 8.8.4)
\par Headers:
    netdb.h
\return pointer to servent or NULL end of database (errno not set)
*/
struct servent *getservent(void);
/**
\par Description:
Get session ID
(Std. UNIX; see AUP2 Sec. 4.3.2)
\par Headers:
    unistd.h
\return session ID or -1 on error (sets errno)
*/
pid_t getsid(
pid_t pid   /**< process ID or 0 for calling process*/
);
/**
\par Description:
Get socket address
(Std. UNIX; see AUP2 Sec. 8.9.2)
\par Headers:
    sys/socket.h
\return 0 on success or -1 on error (sets errno)
*/
int getsockname(
int socket_fd,  /**< socket file descriptor*/
struct sockaddr *sa,    /**< socket address*/
socklen_t *sa_len   /**< address length*/
);
/**
\par Description:
Get the socket options
(Std. UNIX; see AUP2 Sec. 8.3)
\par Headers:
    sys/socket.h
\return 0 on success or -1 on error (sets errno)
*/
int getsockopt(
int socket, /**< socket*/
int level,  /**< level to be accessed*/
int option, /**< option to set*/
const void *value,  /**< value to set*/
socklen_t *value_len    /**< length of value*/
);
/**
\par Description:
Get current date and time as timeval
(Std. UNIX; see AUP2 Sec. 1.7.1)
\par Headers:
    sys/time.h
\return 0 on success or -1 (maybe) on error (may set errno)
*/
int gettimeofday(
struct timeval *tvalbuf,    /**< returned time*/
void *dummy /**< always NULL*/
);
/**
\par Description:
Get real user ID
(Std. UNIX; see AUP2 Sec. 5.11)
\par Headers:
    unistd.h
\return user ID (no error return)
*/
uid_t getuid(void);
/**
\par Description:
Convert time_t to UTC broken-down time
(Std. UNIX; see AUP2 Sec. 1.7.1)
\par Headers:
    time.h
\return broken-down time (no error return)
*/
struct tm *gmtime(
const time_t *t /**< time*/
);
/**
\par Description:
Get access to slave side of pty
(Std. UNIX; see AUP2 Sec. 4.10.1)
\par Headers:
    stdlib.h
\return 0 on success or -1 on error (sets errno)
*/
int grantpt(
int fd  /**< file descriptor*/
);
/**
\par Description:
Convert 32-bit value from host to network byte order
(Std. UNIX; see AUP2 Sec. 8.1.4)
\par Headers:
    arpa/inet.h
\return number in network byte order (no error return)
*/
uint32_t htonl(
uint32_t hostnum    /**< 32-bit number in host byte order*/
);
/**
\par Description:
Convert 16-bit value from host to network byte order
(Std. UNIX; see AUP2 Sec. 8.1.4)
\par Headers:
    arpa/inet.h
\return number in network byte order (no error return)
*/
uint16_t htons(
uint16_t hostnum    /**< 16-bit number in host byte order*/
);
/**
\par Description:
Free array allocated by if_nameindex
(Std. UNIX; see AUP2 Sec. 8.8.5)
\par Headers:
    net/if.h
*/
void if_freenameindex(
struct if_nameindex *ptr    /**< pointer to array*/
);
/**
\par Description:
Map network interface index to name
(Std. UNIX; see AUP2 Sec. 8.8.5)
\par Headers:
    net/if.h
\return name or NULL on error (sets errno)
*/
char *if_indextoname(
unsigned ifindex,   /**< interface index*/
char *ifname    /**< interface name*/
);
/**
\par Description:
Get all network interface names and indexes
(Std. UNIX; see AUP2 Sec. 8.8.5)
\par Headers:
    net/if.h
\return array or NULL on error (sets errno)
*/
struct if_nameindex *if_nameindex(void);
/**
\par Description:
Map network interface name to index
(Std. UNIX; see AUP2 Sec. 8.8.5)
\par Headers:
    net/if.h
\return index or 0 on error (errno not set)
*/
unsigned if_nametoindex(
const char *ifname  /**< interface name*/
);
/**
\par Description:
Convert dotted IPv4 address string to integer
(Std. UNIX; see AUP2 Sec. 8.2.3)
\par Headers:
    arpa/inet.h
\return IP address or (in_addr_t)-1 on error (errno not set)
*/
in_addr_t inet_addr(
const char *cp  /**< dotted IP address*/
);
/**
\par Description:
Convert integer IPv4 address to dotted string
(Std. UNIX; see AUP2 Sec. 8.2.3)
\par Headers:
    arpa/inet.h
\return string (no error return)
*/
char *inet_ntoa(
struct in_addr in   /**< integer address*/
);
/**
\par Description:
Convert IPv4 or IPv6 binary addresses to string
(Std. UNIX; see AUP2 Sec. 8.9.5)
\par Headers:
    arpa/inet.h
\return string or NULL on error (sets errno)
*/
const char *inet_ntop(
int domain, /**< AF_INET or AF_INET6*/
const void *src,    /**< pointer to binary address (input)*/
char *dst,  /**< string (output)*/
socklen_t dst_len   /**< length of dst buffer*/
);
/**
\par Description:
Convert IPv4 or IPv6 string addresses to binary
(Std. UNIX; see AUP2 Sec. 8.9.5)
\par Headers:
    arpa/inet.h
\return 1 on success, 0 on invalid string, or -1 on error (sets errno)
*/
int inet_pton(
int domain, /**< AF_INET or AF_INET6*/
const char *src,    /**< string (input)*/
void *dst   /**< buffer for binary address (output)*/
);
/**
\par Description:
Control a character device
(Std. UNIX; see AUP2 Sec. 4.4)
\par Headers:
    ...
\return -1 on error (sets errno); some other value on success
*/
int ioctl(
int fd, /**< file descriptor*/
int req,    /**< request*/
... /**< arguments that depend on request*/
);
/**
\par Description:
Test for a terminal
(Std. UNIX; see AUP2 Sec. 4.7)
\par Headers:
    unistd.h
\return 1 if a terminal and 0 if not (may set errno on 0 return)
*/
int isatty(
int fd  /**< file descriptor*/
);
/**
\par Description:
Generate signal for processes
(Std. UNIX; see AUP2 Sec. 9.1.9)
\par Headers:
    signal.h
\return 0 on success or -1 on error (sets errno)
*/
int kill(
pid_t pid,  /**< process ID or other specification*/
int signum  /**< signal*/
);
/**
\par Description:
Generate signal for process group
(Std. UNIX; see AUP2 Sec. 9.1.9)
\par Headers:
    signal.h
\return 0 on success or -1 on error (sets errno)
*/
int killpg(
pid_t pgrp, /**< process-group ID*/
int signum  /**< signal*/
);
/**
\par Description:
Change owner and group of symbolic link by path
(Std. UNIX; see AUP2 Sec. 3.7.2)
\par Headers:
    unistd.h
\return 0 on success or -1 on error (sets errno)
*/
int lchown(
const char *path,   /**< pathname*/
uid_t uid,  /**< user ID*/
gid_t gid   /**< group ID*/
);
/**
\par Description:
Create hard link
(Std. UNIX; see AUP2 Sec. 3.3.1)
\par Headers:
    unistd.h
\return 0 on success or -1 on error (sets errno)
*/
int link(
const char *oldpath,    /**< old pathname*/
const char *newpath /**< new pathname*/
);
/**
\par Description:
List-directed I/O
(Std. UNIX; see AUP2 Sec. 3.9.9)
\par Headers:
    aio.h
\return 0 on success or -1 on error (sets errno)
*/
int lio_listio(
int mode,   /**< LIO_WAIT or LIO_NOWAIT*/
struct aiocb *const list[], /**< array of control blocks*/
int cbcnt,  /**< number of elements in array*/
struct sigevent *sig    /**< NULL or signal to generate*/
);
/**
\par Description:
Mark socket for accepting and set queue limit
(Std. UNIX; see AUP2 Sec. 8.1.2)
\par Headers:
    sys/socket.h
\return 0 on success or -1 on error (sets errno)
*/
int listen(
int socket_fd,  /**< socket file descriptor*/
int backlog /**< maximum connection queue length*/
);
/**
\par Description:
Convert time_t to local broken-down time
(Std. UNIX; see AUP2 Sec. 1.7.1)
\par Headers:
    time.h
\return broken-down time (no error return)
*/
struct tm *localtime(
const time_t *t /**< time*/
);
/**
\par Description:
Lock section of file
(Std. UNIX; see AUP2 Sec. 7.11.3)
\par Headers:
    unistd.h
\return 0 on success or -1 on error (sets errno)
*/
int lockf(
int fd, /**< file descriptor*/
int op, /**< operation*/
off_t len   /**< length of section*/
);
/**
\par Description:
Jump to jump point
(Std. UNIX; see AUP2 Sec. 9.6)
\par Headers:
    setjmp.h
*/
void longjmp(
jmp_buf loc_info,   /**< saved location information*/
int val /**< value for setjmp to return*/
);
/**
\par Description:
Set and get file offset
(Std. UNIX; see AUP2 Sec. 2.13)
\par Headers:
    unistd.h
\return new file offset or -1 on error (sets errno)
*/
off_t lseek(
int fd, /**< file descriptor*/
off_t pos,  /**< position*/
int whence  /**< interpretation*/
);
/**
\par Description:
Get file info by path without following symbolic link
(Std. UNIX; see AUP2 Sec. 3.5.1)
\par Headers:
    sys/stat.h
\return 0 on success or -1 on error (sets errno)
*/
int lstat(
const char *path,   /**< pathname*/
struct stat *buf    /**< returned information*/
);
/**
\par Description:
Make directory
(Std. UNIX; see AUP2 Sec. 3.6.3)
\par Headers:
    sys/stat.h
\return 0 on success or -1 on error (sets errno)
*/
int mkdir(
const char *path,   /**< pathname*/
mode_t perms    /**< permissions*/
);
/**
\par Description:
Make a FIFO
(Std. UNIX; see AUP2 Sec. 7.2.1)
\par Headers:
    sys/stat.h
\return 0 on success or -1 on error (sets errno)
*/
int mkfifo(
const char *path,   /**< pathname*/
mode_t perms    /**< permissions*/
);
/**
\par Description:
Make file
(Std. UNIX; see AUP2 Sec. 3.8.2)
\par Headers:
    sys/stat.h
\return 0 on success or -1 on error (sets errno)
*/
int mknod(
const char *path,   /**< pathname*/
mode_t perms,   /**< mode*/
dev_t dev   /**< device-ID*/
);
/**
\par Description:
Create and open file with unique name
(Std. UNIX; see AUP2 Sec. 2.7)
\par Headers:
    stdlib.h
\return open file descriptor or -1 on error (may not set errno)
*/
int mkstemp(
char *template  /**< template for file name*/
);
/**
\par Description:
Convert local broken-down time to time_t
(Std. UNIX; see AUP2 Sec. 1.7.1)
\par Headers:
    time.h
\return time or -1 on error (errno not set)
*/
time_t mktime(
struct tm *tmbuf    /**< broken-down time*/
);
/**
\par Description:
Map pages of memory
(Std. UNIX; see AUP2 Sec. 7.14.1)
\par Headers:
    sys/mman.h
\return pointer to segment or MAP_FAILED on error (sets errno)
*/
void *mmap(
void *addr, /**< desired address or NULL*/
size_t len, /**< length of segment*/
int prot,   /**< protection (see below)*/
int flags,  /**< flags*/
int fd, /**< file descriptor*/
off_t off   /**< offset in file or shared-memory object*/
);
/**
\par Description:
Mount file system (non-standard)
(Std. UNIX; see AUP2 Sec. 3.2.4)
\par Headers:
    sys/mount.h
\return 0 on success or -1 on error (sets errno)
*/
int mount(
const char *source, /**< device*/
const char *target, /**< directory*/
const char *type,   /**< type (e.g., ext2)*/
unsigned long flags,    /**< mount flags (e.g., MS_RDONLY)*/
const void *data    /**< file-system-dependent data*/
);
/**
\par Description:
Close message queue
(Std. UNIX; see AUP2 Sec. 7.7.1)
\par Headers:
    mqueue.h
\return zero on success or -1 on error (sets errno)
*/
int mq_close(
mqd_t mqd   /**< message-queue descriptor*/
);
/**
\par Description:
Get message-queue attributes
(Std. UNIX; see AUP2 Sec. 7.7.1)
\par Headers:
    mqueue.h
\return 0 on success or -1 on error (sets errno)
*/
int mq_getattr(
mqd_t mqd,  /**< message-queue descriptor*/
struct mq_attr *attr    /**< attributes*/
);
/**
\par Description:
Register or unregister for message notification
(Std. UNIX; see AUP2 Sec. 7.7.1)
\par Headers:
    mqueue.h
\return 0 on success or -1 on error (sets errno)
*/
int mq_notify(
mqd_t mqd,  /**< message-queue descriptor*/
const struct sigevent *ep   /**< notification*/
);
/**
\par Description:
Open message-queue
(Std. UNIX; see AUP2 Sec. 7.7.1)
<p>mqd_t mq_open(
<br>const char *name,       POSIX IPC name 
<br>int flags,      flags (including O_CREAT) 
<br>mode_t perms,       permissions 
<br>struct mq_attr *attr        attributes (or NULL) 
<br>);
\par Headers:
    mqueue.h
\return message-queue descriptor or -1 on error (sets errno)
*/
mqd_t mq_open(
const char *name,   /**< POSIX IPC name*/
int flags   /**< flags (excluding O_CREAT)*/
);
/**
\par Description:
Receive message
(Std. UNIX; see AUP2 Sec. 7.7.1)
\par Headers:
    mqueue.h
\return size of message or -1 on error (sets errno)
*/
ssize_t mq_receive(
mqd_t mqd,  /**< message-queue descriptor*/
char *msg,  /**< message buffer*/
size_t msgsize, /**< size of message buffer*/
unsigned *priorityp /**< returned priority or NULL*/
);
/**
\par Description:
Send message
(Std. UNIX; see AUP2 Sec. 7.7.1)
\par Headers:
    mqueue.h
\return 0 on success or -1 on error (sets errno)
*/
int mq_send(
mqd_t mqd,  /**< message-queue descriptor*/
const char *msg,    /**< message*/
size_t msgsize, /**< size of message*/
unsigned priority   /**< priority*/
);
/**
\par Description:
Set message queue attributes (<b>REALTIME</b>)
(Std. UNIX; see AUP2 Sec. 7.7.1)
\par Headers:
    mqueue.h
\return 0 on success or -1 on error (sets errno)
*/
int mq_setattr(
mqd_t mqd,  /**< message-queue descriptor*/
const struct mq_attr *attr, /**< new attributes*/
struct mq_attr *oldattr /**< old attributes*/
);
/**
\par Description:
Receive message with timeout
(Std. UNIX; see AUP2 Sec. 7.7.1)
\par Headers:
    mqueue.h
    , mqueue.h
    , time.h
\return size of message or -1 on error (sets errno)
*/
ssize_t mq_timedreceive(
mqd_t mqd,  /**< message-queue descriptor*/
char *msg,  /**< message buffer*/
size_t msgsize, /**< size of message buffer*/
unsigned *priorityp /**< returned priority or NULL*/
const struct timespec *tmout    /**< timeout*/
);
/**
\par Description:
Send message with timeout
(Std. UNIX; see AUP2 Sec. 7.7.1)
\par Headers:
    mqueue.h
    , mqueue.h
    , time.h
\return 0 on success or -1 on error (sets errno)
*/
int mq_timedsend(
mqd_t mqd,  /**< message-queue descriptor*/
const char *msg,    /**< message*/
size_t msgsize, /**< size of message*/
unsigned priority   /**< priority*/
const struct timespec *tmout    /**< timeout*/
);
/**
\par Description:
Remove message queue
(Std. UNIX; see AUP2 Sec. 7.7.1)
\par Headers:
    mqueue.h
\return 0 on success or -1 on error (sets errno)
*/
int mq_unlink(
const char *name    /**< POSIX IPC name*/
);
/**
\par Description:
Control message queue
(Std. UNIX; see AUP2 Sec. 7.5.1)
\par Headers:
    sys/msg.h
\return 0 on success or -1 on error (sets errno)
*/
int msgctl(
int msqid,  /**< identifier*/
int cmd,    /**< command*/
struct msqid_ds *data   /**< data for command*/
);
/**
\par Description:
Get message-queue identifier
(Std. UNIX; see AUP2 Sec. 7.5.1)
\par Headers:
    sys/msg.h
\return identifier or -1 on error (sets errno)
*/
int msgget(
key_t key,  /**< key*/
int flags   /**< creation flags*/
);
/**
\par Description:
Receive message
(Std. UNIX; see AUP2 Sec. 7.5.1)
\par Headers:
    sys/msg.h
\return number of bytes placed in mtext or -1 on error (sets errno)
*/
ssize_t msgrcv(
int msqid,  /**< identifier*/
const void *msgp,   /**< message*/
size_t mtextsize,   /**< size of mtext buffer*/
long msgtype,   /**< message type requested*/
int flags   /**< flags*/
);
/**
\par Description:
Send message
(Std. UNIX; see AUP2 Sec. 7.5.1)
\par Headers:
    sys/msg.h
\return 0 on success or -1 on error (sets errno)
*/
int msgsnd(
int msqid,  /**< identifier*/
const void *msgp,   /**< message*/
size_t msgsize, /**< size of message*/
int flags   /**< flags*/
);
/**
\par Description:
Unmap pages of memory
(Std. UNIX; see AUP2 Sec. 7.14.1)
\par Headers:
    sys/mman.h
\return 0 on success or -1 on error (sets errno)
*/
int munmap(
void *addr, /**< pointer to segment*/
size_t len  /**< length of segment*/
);
/**
\par Description:
Suspend execution for nanoseconds or until signal
(Std. UNIX; see AUP2 Sec. 9.7.3)
\par Headers:
    time.h
\return 0 on success or -1 on error (sets errno)
*/
int nanosleep(
const struct timespec *nsecs,   /**< nanoseconds to sleep*/
struct timespec *remain /**< remaining time*/
);
/**
\par Description:
Change nice value
(Std. UNIX; see AUP2 Sec. 5.15)
\par Headers:
    unistd.h
\return old nice value - NZERO or -1 on error (sets errno)
*/
int nice(
int incr    /**< increment*/
);
/**
\par Description:
Convert 32-bit value from network to host byte order
(Std. UNIX; see AUP2 Sec. 8.1.4)
\par Headers:
    arpa/inet.h
\return number in host byte order (no error return)
*/
uint32_t ntohl(
uint32_t netnum /**< 32-bit number in network byte order*/
);
/**
\par Description:
Convert 16-bit value from network to host byte order
(Std. UNIX; see AUP2 Sec. 8.1.4)
\par Headers:
    arpa/inet.h
\return number in host byte order (no error return)
*/
uint16_t ntohs(
uint16_t netnum /**< 16-bit number in network byte order*/
);
/**
\par Description:
Open or create a file
(Std. UNIX; see AUP2 Sec. 2.4)
\par Headers:
    sys/stat.h
    , fcntl.h
\return file descriptor or -1 on error (sets errno)
*/
int open(
const char *path,   /**< pathname*/
int flags,  /**< flags*/
mode_t perms    /**< permissions (when creating)*/
);
/**
\par Description:
Open directory
(Std. UNIX; see AUP2 Sec. 3.6.1)
\par Headers:
    dirent.h
\return DIR pointer or NULL on error (sets errno)
*/
DIR *opendir(
const char *path    /**< directory pathname*/
);
/**
\par Description:
Get system option or limit by path
(Std. UNIX; see AUP2 Sec. 1.5.6)
\par Headers:
    unistd.h
\return option/limit value or -1 (sets errno on error)
*/
long pathconf(
const char *path,   /**< pathname*/
int name    /**< option or limit name*/
);
/**
\par Description:
Wait for signal
(Std. UNIX; see AUP2 Sec. 9.2.1)
\par Headers:
    unistd.h
\return -1 on error (sets errno)
*/
int pause(void);
/**
\par Description:
Create pipe
(Std. UNIX; see AUP2 Sec. 6.2.1)
\par Headers:
    unistd.h
\return 0 on success or -1 on error (sets errno)
*/
int pipe(
int pfd[2]  /**< file descriptors*/
);
/**
\par Description:
Wait for I/O to be ready
(Std. UNIX; see AUP2 Sec. 4.2.4)
\par Headers:
    poll.h
\return number of ready file descriptors or -1 on error (sets errno)
*/
int poll(
struct pollfd fdinfo[], /**< info on file descriptors to be tested*/
nfds_t nfds,    /**< number of elements in fdinfo array*/
int timeout /**< time-out (milliseconds)*/
);
/**
\par Description:
Open pty
(Std. UNIX; see AUP2 Sec. 4.10.1)
\par Headers:
    stdlib.h
    , fcntl.h
\return 0 on success or -1 on error (sets errno)
*/
int posix_openpt(
int oflag   /**< O_RDWR optionally ORed with O_NOCTTY*/
);
/**
\par Description:
Read from file descriptor at offset
(Std. UNIX; see AUP2 Sec. 2.14)
\par Headers:
    unistd.h
\return number of bytes read or -1 on error (sets errno)
*/
ssize_t pread(
int fd, /**< file descriptor*/
void *buf,  /**< address to receive data*/
size_t nbytes   /**< amount to read*/
off_t offset    /**< where to read*/
);
/**
\par Description:
Wait for I/O to be ready
(Std. UNIX; see AUP2 Sec. 4.2.3)
\par Headers:
    sys/select.h
\return number of bits set or -1 on error (sets errno)
*/
int pselect(
int nfds,      /**< highest fd + 1*/
fd_set *readset,       /**< read set or NULL*/
fd_set *writeset,      /**< write set or NULL*/
fd_set *errorset,      /**< error set or NULL*/
const struct timespec *timeout, /**< time-out (nanoseconds) or NULL*/
const sigset_t *sigmask    /**< signal mask*/
);
/**
\par Description:
Cancel thread
(Std. UNIX; see AUP2 Sec. 5.17.5)
\par Headers:
    pthread.h
\return 0 on success, error number on failure
*/
int pthread_cancel(
pthread_t thread_id /**< ID of thread to cancel*/
);
/**
\par Description:
Uninstall cleanup handler
(Std. UNIX; see AUP2 Sec. 5.17.5)
\par Headers:
    pthread.h
*/
void pthread_cleanup_pop(
int execute /**< execute handler?*/
);
/**
\par Description:
Install cleanup handler
(Std. UNIX; see AUP2 Sec. 5.17.5)
\par Headers:
    pthread.h
*/
void pthread_cleanup_push(
void (*handler)(void*), /**< pointer to cleanup-handler function*/
void *arg   /**< data to pass to function*/
);
/**
\par Description:
Signal condition
(Std. UNIX; see AUP2 Sec. 5.17.4)
\par Headers:
    pthread.h
\return 0 on success, error number on failure
*/
int pthread_cond_signal(
pthread_cond_t *cond    /**< condition variable*/
);
/**
\par Description:
Wait for condition
(Std. UNIX; see AUP2 Sec. 5.17.4)
\par Headers:
    pthread.h
\return 0 on success, error number on failure
*/
int pthread_cond_wait(
pthread_cond_t *cond,   /**< condition variable */ pthread_mutex_t *mutex  /* mutex*/
);
/**
\par Description:
Create a thread
(Std. UNIX; see AUP2 Sec. 5.17.1)
\par Headers:
    pthread.h
\return 0 on success, error number on failure
*/
int pthread_create(
pthread_t *thread_id,   /**< new thread’s ID*/
const pthread_attr_t *attr, /**< attributes (or NULL)*/
void *(*start_fcn)(void *), /**< starting function*/
void *arg   /**< arg to starting function*/
);
/**
\par Description:
Wait for thread to terminate
(Std. UNIX; see AUP2 Sec. 5.17.2)
\par Headers:
    pthread.h
\return 0 on success, error number on failure
*/
int pthread_join(
pthread_t thread_id,    /**< ID of thread to join*/
void **status_ptr   /**< NULL or returned exit status*/
);
/**
\par Description:
Generate signal for thread
(Std. UNIX; see AUP2 Sec. 9.1.9)
\par Headers:
    signal.h
\return 0 on success, error number on failure (errno not set)
*/
int pthread_kill(
pthread_t thread_id,    /**< thread ID*/
int signum  /**< signal*/
);
/**
\par Description:
Lock mutex
(Std. UNIX; see AUP2 Sec. 5.17.3)
\par Headers:
    pthread.h
\return 0 on success, error number on failure
*/
int pthread_mutex_lock(
pthread_mutex_t *mutex  /**< mutex to lock*/
);
/**
\par Description:
Unlock mutex
(Std. UNIX; see AUP2 Sec. 5.17.3)
\par Headers:
    pthread.h
\return 0 on success, error number on failure
*/
int pthread_mutex_unlock(
pthread_mutex_t *mutex  /**< mutex to unlock*/
);
/**
\par Description:
Change thread’s signal mask
(Std. UNIX; see AUP2 Sec. 9.1.5)
\par Headers:
\return 0 on success, error number on failure (errno not set)
*/
int pthread_sigmask(
int how,    /**< how signal mask is to be changed*/
const sigset_t *set,    /**< input set*/
sigset_t *oset  /**< previous signal mask*/
);
/**
\par Description:
Test for cancellation
(Std. UNIX; see AUP2 Sec. 5.17.5)
\par Headers:
    pthread.h
*/
void pthread_testcancel(void);
/**
\par Description:
Get name of slave side of pty
(Std. UNIX; see AUP2 Sec. 4.10.1)
\par Headers:
    stdlib.h
\return name or NULL on error (errno not set)
*/
char *ptsname(
int fd  /**< file descriptor*/
);
/**
\par Description:
Change or add to environment
(Std. UNIX; see AUP2 Sec. 5.2)
\par Headers:
    stdlib.h
\return 0 on success or non-zero on error (sets errno)
*/
int putenv(
char *string    /**< string of form name=value*/
);
/**
\par Description:
Write to file descriptor at offset
(Std. UNIX; see AUP2 Sec. 2.14)
\par Headers:
    unistd.h
\return number of bytes written or -1 on error (sets errno)
*/
ssize_t pwrite(
int fd, /**< file descriptor*/
const void *buf,    /**< data to write*/
size_t nbytes   /**< amount to write*/
off_t offset    /**< where to write*/
);
/**
\par Description:
Generate signal for process
(Std. UNIX; see AUP2 Sec. 9.1.9)
\par Headers:
    signal.h
\return 0 on success or non-zero on error (sets errno)
*/
int raise(
int signum  /**< signal*/
);
/**
\par Description:
Read from file descriptor
(Std. UNIX; see AUP2 Sec. 2.10)
\par Headers:
    unistd.h
\return number of bytes read or -1 on error (sets errno)
*/
ssize_t read(
int fd, /**< file descriptor*/
void *buf,  /**< address to receive data*/
size_t nbytes   /**< amount to read*/
);
/**
\par Description:
Read directory
(Std. UNIX; see AUP2 Sec. 3.6.1)
\par Headers:
    dirent.h
\return structure or NULL on EOF or error (sets errno)
*/
struct dirent *readdir(
DIR *dirp   /**< DIR pointer from opendir*/
);
/**
\par Description:
Read a directory
(Std. UNIX; see AUP2 Sec. 3.6.1)
\par Headers:
    dirent.h
\return 0 on success or error number on error (sets errno)
*/
int readdir_r(
DIR *restrict dirp, /**< DIR pointer from opendir*/
struct dirent *entry,   /**< structure to hold entry*/
struct dirent **result  /**< result (pointer or NULL)*/
);
/**
\par Description:
Read a symbolic link
(Std. UNIX; see AUP2 Sec. 3.3.3)
\par Headers:
    unistd.h
\return byte count or -1 on error (sets errno)
*/
ssize_t readlink(
const char *path,   /**< pathname*/
char *buf,  /**< returned text*/
size_t bufsize  /**< buffer size*/
);
/**
\par Description:
Scatter read
(Std. UNIX; see AUP2 Sec. 2.15)
\par Headers:
    sys/uio.h
\return number of bytes read or -1 on error (sets errno) 
*/
ssize_t readv(
int fd, /**< file descriptor*/
const struct iovec *iov,    /**< vector of data buffers*/
int iovcnt  /**< number of elements*/
);
/**
\par Description:
Receive data from socket
(Std. UNIX; see AUP2 Sec. 8.9.1)
\par Headers:
    sys/socket.h
\return number of bytes received, 0, or -1 on error (sets errno)
*/
ssize_t recv(
int socket_fd,  /**< socket file descriptor*/
void *buffer,   /**< buffer to receive data*/
size_t length,  /**< length of buffer*/
int flags   /**< flags*/
);
/**
\par Description:
Receive message from socket
(Std. UNIX; see AUP2 Sec. 8.6.2)
\par Headers:
    sys/socket.h
\return number of bytes received, 0, or -1 on error (sets errno)
*/
ssize_t recvfrom(
int socket_fd,  /**< socket file descriptor*/
void *buffer,   /**< buffer for received message*/
size_t length,  /**< length of buffer*/
int flags,  /**< flags*/
struct sockaddr *sa,    /**< address of sender*/
socklen_t *sa_len   /**< address length*/
);
/**
\par Description:
Receive a message from a socket
(Std. UNIX; see AUP2 Sec. 8.6.3)
\par Headers:
    sys/socket.h
\return number of bytes received, 0, or -1 on error (sets errno)
*/
ssize_t recvmsg(
int socket_fd,  /**< socket file descriptor*/
struct msghdr *message, /**< message*/
int flags   /**< flags*/
);
/**
\par Description:
Rename a file
(Std. UNIX; see AUP2 Sec. 3.3.2)
\par Headers:
    stdio.h
\return 0 on success or -1 on error (sets errno)
*/
int rename(
const char *oldpath,    /**< old pathname*/
const char *newpath /**< new pathname*/
);
/**
\par Description:
Rewind directory
(Std. UNIX; see AUP2 Sec. 3.6.1)
\par Headers:
    dirent.h
*/
void rewinddir(
DIR *dirp   /**< DIR pointer from opendir*/
);
/**
\par Description:
Remove directory
(Std. UNIX; see AUP2 Sec. 3.6.3)
\par Headers:
    unistd.h
\return 0 on success or -1 on error (sets errno)
*/
int rmdir(
const char *path    /**< pathname*/
);
/**
\par Description:
Seek directory
(Std. UNIX; see AUP2 Sec. 3.6.1)
\par Headers:
    dirent.h
*/
void seekdir(
DIR *dirp,  /**< DIR pointer from opendir*/
long loc    /**< location*/
);
/**
\par Description:
Wait for I/O to be ready
(Std. UNIX; see AUP2 Sec. 4.2.3)
\par Headers:
    sys/select.h
\return number of bits set or -1 on error (sets errno)
*/
int select(
int nfds,      /**< highest fd + 1*/
fd_set *readset,       /**< read set or NULL*/
fd_set *writeset,      /**< write set or NULL*/
fd_set *errorset,      /**< error set or NULL*/
struct timeval *timeout    /**< time-out (microseconds) or NULL*/
);
/**
\par Description:
Close named semaphore
(Std. UNIX; see AUP2 Sec. 7.10.1)
\par Headers:
    semaphore.h
\return 0 on success or -1 on error (sets errno)
*/
int sem_close(
sem_t *sem  /**< semaphore*/
);
/**
\par Description:
Destroy unnamed semaphore
(Std. UNIX; see AUP2 Sec. 7.10.2)
\par Headers:
    semaphore.h
\return 0 on success or -1 on error (sets errno)
*/
int sem_destroy(
sem_t *sem  /**< semaphore*/
);
/**
\par Description:
Get value of semaphore
(Std. UNIX; see AUP2 Sec. 7.10.1)
\par Headers:
    semaphore.h
\return 0 on success or -1 on error (sets errno)
*/
int sem_getvalue(
sem_t *restrict sem,    /**< semaphpre*/
int *valuep /**< returned value*/
);
/**
\par Description:
Initialize unnamed semaphore
(Std. UNIX; see AUP2 Sec. 7.10.2)
\par Headers:
    semaphore.h
\return 0 on success or -1 on error (sets errno)
*/
int sem_init(
sem_t *sem, /**< semaphore*/
int pshared,    /**< shared between processes?*/
unsigned value  /**< initial value*/
);
/**
\par Description:
Open named semaphore
(Std. UNIX; see AUP2 Sec. 7.10.1)
<p>sem_t *sem_open(
<br>const char *name,       POSIX IPC name 
<br>int flags,      flags (including O_CREAT) 
<br>mode_t perms,       permissions 
<br>unsigned value      initial value 
<br>);
\par Headers:
    semaphore.h
\return pointer to semaphore or SEM_FAILED on error (sets errno)
*/
sem_t *sem_open(
const char *name,   /**< POSIX IPC name*/
int flags   /**< flags (excluding O_CREAT)*/
);
/**
\par Description:
Increment semaphore
(Std. UNIX; see AUP2 Sec. 7.10.1)
\par Headers:
    semaphore.h
\return 0 on success or -1 on error (sets errno)
*/
int sem_post(
sem_t *sem  /**< semaphore*/
);
/**
\par Description:
Decrement semaphore
(Std. UNIX; see AUP2 Sec. 7.10.1)
\par Headers:
    semaphore.h
    , time.h
\return 0 on success or -1 on error (sets errno)
*/
int sem_timedwait(
sem_t *restrict sem,    /**< semaphore*/
const struct timespec *time /**< absolute time*/
);
/**
\par Description:
Decrement semaphore if possible
(Std. UNIX; see AUP2 Sec. 7.10.1)
\par Headers:
    semaphore.h
\return 0 on success or -1 on error (sets errno)
*/
int sem_trywait(
sem_t *sem  /**< semaphore*/
);
/**
\par Description:
Remove named semaphore
(Std. UNIX; see AUP2 Sec. 7.10.1)
\par Headers:
    semaphore.h
\return 0 on success or -1 on error (sets errno)
*/
int sem_unlink(
const char *name    /**< POSIX IPC name*/
);
/**
\par Description:
Decrement semaphore
(Std. UNIX; see AUP2 Sec. 7.10.1)
\par Headers:
    semaphore.h
\return 0 on success or -1 on error (sets errno)
*/
int sem_wait(
sem_t *sem  /**< semaphore*/
);
/**
\par Description:
Control semaphore set
(Std. UNIX; see AUP2 Sec. 7.9.1)
\par Headers:
    sys/sem.h
\return value or 0 on success; -1 on error (sets errno)
*/
int semctl(
int semid,  /**< identifier*/
int semnum, /**< semaphore number*/
int cmd,    /**< command*/
union semun arg /**< argument for command*/
);
/**
\par Description:
Get semaphore-set identifier
(Std. UNIX; see AUP2 Sec. 7.9.1)
\par Headers:
    sys/sem.h
\return identifier or -1 on error (sets errno)
*/
int semget(
key_t key,  /**< key*/
int nsems,  /**< size of set*/
int flags   /**< flags*/
);
/**
\par Description:
Operate on semaphore set
(Std. UNIX; see AUP2 Sec. 7.9.2)
\par Headers:
    sys/sem.h
\return 0 on success or -1 on error (sets errno)
*/
int semop(
int semid,  /**< identifier*/
struct sembuf *sops,    /**< operations*/
size_t nsops    /**< number of operations*/
);
/**
\par Description:
Send data to socket
(Std. UNIX; see AUP2 Sec. 8.9.1)
\par Headers:
    sys/socket.h
\return number of bytes sent or -1 on error (sets errno)
*/
ssize_t send(
int socket_fd,  /**< socket file descriptor*/
const void *data,   /**< data to send*/
size_t length,  /**< length of data*/
int flags   /**< flags*/
);
/**
\par Description:
Send a message on a socket using a message structure
(Std. UNIX; see AUP2 Sec. 8.6.3)
\par Headers:
    sys/socket.h
\return number of bytes sent or -1 on error (sets errno)
*/
ssize_t sendmsg(
int socket_fd,  /**< socket file descriptor*/
const struct msghdr *message,   /**< message*/
int flags   /**< flags*/
);
/**
\par Description:
Send message to socket
(Std. UNIX; see AUP2 Sec. 8.6.2)
\par Headers:
    sys/socket.h
\return number of bytes sent or -1 on error (sets errno)
*/
ssize_t sendto(
int socket_fd,  /**< socket file descriptor*/
const void *message,    /**< message to send*/
size_t length,  /**< length of message*/
int flags,  /**< flags*/
const struct sockaddr *sa,  /**< target address*/
socklen_t sa_len    /**< length of target address*/
);
/**
\par Description:
Set effective group ID
(Std. UNIX; see AUP2 Sec. 5.12)
\par Headers:
    unistd.h
\return 0 on success or -1 on error (sets errno)
*/
int setegid(
gid_t gid   /**< effective group ID*/
);
/**
\par Description:
Change or add to environment
(Std. UNIX; see AUP2 Sec. 5.2)
\par Headers:
    stdlib.h
\return 0 on success or -1 on error (sets errno)
*/
int setenv(
const char *var,    /**< variable to be changed or added*/
const char *val,    /**< value*/
int overwrite   /**< overwrite?*/
);
/**
\par Description:
Set effective user ID
(Std. UNIX; see AUP2 Sec. 5.12)
\par Headers:
    unistd.h
\return 0 on success or -1 on error (sets errno)
*/
int seteuid(
uid_t uid   /**< effective user ID*/
);
/**
\par Description:
Set real, effective, and saved group ID
(Std. UNIX; see AUP2 Sec. 5.12)
\par Headers:
    unistd.h
\return 0 on success or -1 on error (sets errno)
*/
int setgid(
gid_t gid   /**< real and saved group ID*/
);
/**
\par Description:
Start host-database scan
(Std. UNIX; see AUP2 Sec. 8.8.1)
\par Headers:
    netdb.h
*/
void sethostent(
int stayopen    /**< leave connection open?*/
);
/**
\par Description:
Set value of interval timer
(Std. UNIX; see AUP2 Sec. 9.7.4)
\par Headers:
    sys/time.h
\return 0 on success or -1 on error (sets errno)
*/
int setitimer(
int which,  /**< timer to set*/
const struct itimerval *val,    /**< value to set*/
struct itimerval *oval  /**< returned old value*/
);
/**
\par Description:
Set jump point
(Std. UNIX; see AUP2 Sec. 9.6)
\par Headers:
    setjmp.h
\return 0 if called directly, non-zero if from longjmp (no error return)
*/
int setjmp(
jmp_buf loc_info    /**< saved location information*/
);
/**
\par Description:
Start network-database scan
(Std. UNIX; see AUP2 Sec. 8.8.2)
\par Headers:
    netdb.h
*/
void setnetent(
int stayopen    /**< leave connection open?*/
);
/**
\par Description:
Set or create process-group
(Std. UNIX; see AUP2 Sec. 4.3.3)
\par Headers:
    unistd.h
\return 0 on success or -1 on error (sets errno)
*/
int setpgid(
pid_t pid,  /**< process ID or 0 for calling process*/
pid_t pgid  /**< process-group ID*/
);
/**
\par Description:
Start protocol-database scan
(Std. UNIX; see AUP2 Sec. 8.8.3)
\par Headers:
    netdb.h
*/
void setprotoent(
int stayopen    /**< leave connection open?*/
);
/**
\par Description:
Set resource limits
(Std. UNIX; see AUP2 Sec. 5.16)
\par Headers:
    sys/resource.h
\return 0 on success or -1 on error (sets errno)
*/
int setrlimit(
int resource,   /**< resource*/
const struct rlimit *rlp    /**< limits to set*/
);
/**
\par Description:
Start service-database scan
(Std. UNIX; see AUP2 Sec. 8.8.4)
\par Headers:
    netdb.h
*/
void setservent(
int stayopen    /**< leave connection open?*/
);
/**
\par Description:
Create session and process group
(Std. UNIX; see AUP2 Sec. 4.3.2)
\par Headers:
    unistd.h
\return process-group ID or -1 on error (sets errno)
*/
pid_t setsid(void);
/**
\par Description:
Set the socket options
(Std. UNIX; see AUP2 Sec. 8.3)
\par Headers:
    sys/socket.h
\return 0 on success or -1 on error (sets errno)
*/
int setsockopt(
int socket_fd,  /**< socket file descriptor*/
int level,  /**< level to be accessed*/
int option, /**< option to set*/
const void *value,  /**< value to set*/
socklen_t value_len /**< length of value*/
);
/**
\par Description:
Set real, effective, and saved user ID
(Std. UNIX; see AUP2 Sec. 5.12)
\par Headers:
    unistd.h
\return 0 on success or -1 on error (sets errno)
*/
int setuid(
uid_t uid   /**< real and saved user ID*/
);
/**
\par Description:
Open shared-memory object
(Std. UNIX; see AUP2 Sec. 7.14.1)
\par Headers:
    sys/mman.h
\return file descriptor or -1 on error (sets errno)
*/
int shm_open(
const char *name,   /**< POSIX IPC name*/
int flags,  /**< flags*/
mode_t perms    /**< permissions*/
);
/**
\par Description:
Remove shared-memory object
(Std. UNIX; see AUP2 Sec. 7.14.1)
\par Headers:
    sys/mman.h
\return 0 on success or -1 on error (sets errno)
*/
int shm_unlink(
const char *name    /**< POSIX IPC name*/
);
/**
\par Description:
Attach shared memory segment
(Std. UNIX; see AUP2 Sec. 7.13.1)
\par Headers:
    sys/shm.h
\return pointer or -1 on error (sets errno)
*/
void *shmat(
int shmid,  /**< identifier*/
const void *shmaddr,    /**< desired address or NULL*/
int flags   /**< attachment flags*/
);
/**
\par Description:
Control shared memory segment
(Std. UNIX; see AUP2 Sec. 7.13.1)
\par Headers:
    sys/shm.h
\return 0 on success or -1 on error (sets errno)
*/
int shmctl(
int shmid,  /**< identifier*/
int cmd,    /**< command*/
struct shmid_ds *data   /**< data for command*/
);
/**
\par Description:
Detach shared memory segment
(Std. UNIX; see AUP2 Sec. 7.13.1)
\par Headers:
    sys/shm.h
\return 0 on success or -1 on error (sets errno)
*/
int shmdt(
const void *shmaddr /**< pointer to segment*/
);
/**
\par Description:
Get shared memory segment
(Std. UNIX; see AUP2 Sec. 7.13.1)
\par Headers:
    sys/shm.h
\return shared-memory identifier or -1 on error (sets errno)
*/
int shmget(
key_t key,  /**< key*/
size_t size,    /**< size of segment*/
int flags   /**< creation flags*/
);
/**
\par Description:
Shut down socket send and/or receive operations
(Std. UNIX; see AUP2 Sec. 8.9.4)
\par Headers:
    sys/socket.h
\return 0 on success or -1 on error (sets errno)
*/
int shutdown(
int socket_fd,  /**< socket file descriptor*/
int how /**< SHUT_RD, SHUT_WR, or SHUT_RDWR*/
);
/**
\par Description:
Set signal action
(Std. UNIX; see AUP2 Sec. 9.1.6)
\par Headers:
    signal.h
\return 0 on success or -1 on error (sets errno)
*/
int sigaction(
int signum, /**< signal*/
const struct sigaction *act,    /**< new action*/
struct sigaction *oact  /**< old action*/
);
/**
\par Description:
Add signal to signal set
(Std. UNIX; see AUP2 Sec. 9.1.5)
\par Headers:
    signal.h
\return 0 on success or -1 on error (sets errno)
*/
int sigaddset(
sigset_t *set,  /**< signal set*/
int signum  /**< signal*/
);
/**
\par Description:
Set and get alternate stack context
(Std. UNIX; see AUP2 Sec. 9.3)
\par Headers:
    signal.h
\return 0 on success or -1 on error (sets errno)
*/
int sigaltstack(
const stack_t *stack,   /**< new stack*/
stack_t *ostack /**< old stack*/
);
/**
\par Description:
Delete a signal from a signal set
(Std. UNIX; see AUP2 Sec. 9.1.5)
\par Headers:
    signal.h
\return 0 on success or -1 on error (sets errno)
*/
int sigdelset(
sigset_t *set,  /**< signal set*/
int signum  /**< signal*/
);
/**
\par Description:
Initialize empty signal set
(Std. UNIX; see AUP2 Sec. 9.1.5)
\par Headers:
    signal.h
\return 0 on success or -1 on error (sets errno)
*/
int sigemptyset(
sigset_t *set   /**< signal set*/
);
/**
\par Description:
Initialize full signal set
(Std. UNIX; see AUP2 Sec. 9.1.5)
\par Headers:
    signal.h
\return 0 on success or -1 on error (sets errno)
*/
int sigfillset(
sigset_t *set   /**< signal set*/
);
/**
\par Description:
Block a signal
(Std. UNIX; see AUP2 Sec. 9.4)
\par Headers:
    signal.h
\return 0 on success or -1 on error (sets errno)
*/
int sighold(
int signum, /**< signal*/
);
/**
\par Description:
Ignore signal
(Std. UNIX; see AUP2 Sec. 9.4)
\par Headers:
    signal.h
\return 0 on success or -1 on error (sets errno)
*/
int sigignore(
int signum, /**< signal*/
);
/**
\par Description:
Structure for sigaction and waitid
(Std. UNIX; see AUP2 Sec. 5.8 and 9.5.1)
\par Headers:
*/
typedef struct {
int si_signo;   /**< signal number*/
int si_errno;   /**< errno value associated with signal*/
int si_code;    /**< signal code (see below)*/
pid_t si_pid;   /**< sending process ID*/
uid_t si_uid;   /**< real user ID of sending process*/
void *si_addr;  /**< address of faulting instruction*/
int si_status;  /**< exit value or signal*/
long si_band;   /**< band event for SIGPOLL*/
union sigval si_value;  /**< signal value*/
} siginfo_t;
/**
\par Description:
Set or clear SA_RESTART flag
(Std. UNIX; see AUP2 Sec. 9.3)
\par Headers:
    signal.h
\return 0 on success or -1 on error (sets errno)
*/
int siginterrupt(
int signum, /**< signal*/
int flag  /**< non-zero to clear, zero to set*/
);
/**
\par Description:
Test for signal in signal set
(Std. UNIX; see AUP2 Sec. 9.1.5)
\par Headers:
    signal.h
\return 1 if member, 0 if not, or -1 on error (sets errno)
*/
int sigismember(
const sigset_t *set,    /**< signal set*/
int signum  /**< signal*/
);
/**
\par Description:
Jump to jump point, restore signal mask if saved
(Std. UNIX; see AUP2 Sec. 9.6)
\par Headers:
    setjmp.h
*/
void siglongjmp(
sigjmp_buf loc_info,    /**< saved location information*/
int val /**< value for sigsetjmp to return*/
);
/**
\par Description:
Set signal action
(Std. UNIX; see AUP2 Sec. 9.4)
\par Headers:
    signal.h
\return old action or SIG_ERR on error (sets errno)
*/
void (*signal(
int signum, /**< signal*/
void (*act)(int)    /**< new action*/
))(int);
/**
\par Description:
Change signal mask and wait for signal
(Std. UNIX; see AUP2 Sec. 9.4)
\par Headers:
    signal.h
\return -1 on error, always (sets errno)
*/
int sigpause(
int signum, /**< signal*/
);
/**
\par Description:
Examine pending signals
(Std. UNIX; see AUP2 Sec. 9.3)
\par Headers:
    signal.h
\return 0 on success or -1 on error (sets errno)
*/
int sigpending(
sigset_t *set   /**< returned set of pending signals*/
);
/**
\par Description:
Change thread’s signal mask (single thread only)
(Std. UNIX; see AUP2 Sec. 9.1.5)
\par Headers:
    signal.h
\return 0 on success or -1 on error (sets errno)
*/
int sigprocmask(
int how,    /**< how signal mask is to be changed*/
const sigset_t *set,    /**< input set*/
sigset_t *oset  /**< previous signal mask*/
);
/**
\par Description:
Generate signal for process
(Std. UNIX; see AUP2 Sec. 9.5.4)
\par Headers:
    signal.h
\return 0 on success or -1 on error (sets errno)
*/
int sigqueue(
pid_t pid,  /**< process ID*/
int signum, /**< signal*/
const union sigval value    /**< value*/
);
/**
\par Description:
Unblock signal
(Std. UNIX; see AUP2 Sec. 9.4)
\par Headers:
    signal.h
\return 0 on success or -1 on error (sets errno)
*/
int sigrelse(
int signum, /**< signal*/
);
/**
\par Description:
Signal management
(Std. UNIX; see AUP2 Sec. 9.4)
\par Headers:
    signal.h
\return old action or SIG_ERR on error (sets errno)
*/
void (*sigset(
int signum, /**< signal*/
void (*act)(int)    /**< new action*/
))(int);
/**
\par Description:
Set jump point
(Std. UNIX; see AUP2 Sec. 9.6)
\par Headers:
    setjmp.h
\return 0 if called directly, non-zero if from siglongjmp (no error return)
*/
int sigsetjmp(
sigjmp_buf loc_info,    /**< saved location information*/
int savemask    /**< non-zero to save signal mask*/
);
/**
\par Description:
Change signal mask and wait for signal
(Std. UNIX; see AUP2 Sec. 9.2.3)
\par Headers:
    signal.h
\return -1 on error, always (sets errno)
*/
int sigsuspend(
const sigset_t *sigmask /**< temporary signal mask*/
);
/**
\par Description:
Wait for signal
(Std. UNIX; see AUP2 Sec. 9.5.5)
\par Headers:
    signal.h
\return signal number or -1 on error (sets errno)
*/
int sigtimedwait(
const sigset_t *set,    /**< signals to wait for*/
siginfo_t *info,    /**< returned info*/
const struct timespec *ts   /**< max. time to wait*/
);
/**
\par Description:
Wait for signal
(Std. UNIX; see AUP2 Sec. 9.2.2)
\par Headers:
    signal.h
\return 0 on success or error number on error
*/
int sigwait(
const sigset_t *set,    /**< signals to wait for*/
int *signum /**< signal that was delivered*/
);
/**
\par Description:
Wait for signal
(Std. UNIX; see AUP2 Sec. 9.5.5)
\par Headers:
    signal.h
\return signal number or -1 on error (sets errno)
*/
int sigwaitinfo(
const sigset_t *set,    /**< signals to wait for*/
siginfo_t *info /**< returned info*/
);
/**
\par Description:
Suspend execution for seconds or until signal
(Std. UNIX; see AUP2 Sec. 9.7.2)
\par Headers:
    unistd.h
\return unslept amount
*/
unsigned sleep(
unsigned secs   /**< seconds to sleep*/
);
/**
\par Description:
Test presence of out-of-band mark
(Std. UNIX; see AUP2 Sec. 8.7)
\par Headers:
    sys/socket.h
\return 1 if at mark, 0 if not, or -1 on error (sets errno)
*/
int sockatmark(
int socket_fd,  /**< socket file descriptor*/
);
/**
\par Description:
Create endpoint for communication
(Std. UNIX; see AUP2 Sec. 8.1.2)
\par Headers:
    sys/socket.h
\return file descriptor or -1 on error (sets errno)
*/
int socket(
int domain, /**< domain (AF_UNIX, AF_INET, etc.)*/
int type,   /**< SOCK_STREAM, SOCK_DGRAM, etc.*/
int protocol    /**< specific to type; usually zero*/
);
/**
\par Description:
Create pair of sockets
(Std. UNIX; see AUP2 Sec. 8.9.3)
\par Headers:
    sys/socket.h
\return 0 on success or -1 on error (sets errno)
*/
int socketpair(
int domain, /**< domain (AF_UNIX, AF_INET, etc.)*/
int type,   /**< SOCK_STREAM, SOCK_DGRAM, etc.*/
int protocol    /**< specific to type; usually zero*/
int socket_vector[2]    /**< returned socket file descriptors*/
);
/**
\par Description:
Get file info by path
(Std. UNIX; see AUP2 Sec. 3.5.1)
\par Headers:
    sys/stat.h
\return 0 on success or -1 on error (sets errno)
*/
int stat(
const char *path,   /**< pathname*/
struct stat *buf    /**< returned information*/
);
/**
\par Description:
Get file system information by path
(Std. UNIX; see AUP2 Sec. 3.2.3)
\par Headers:
    sys/statvfs.h
\return 0 on success or -1 on error (sets errno)
*/
int statvfs(
const char *path    /**< pathname*/
struct statvfs *buf /**< returned info*/
);
/**
\par Description:
Convert broken-down time to string with format
(Std. UNIX; see AUP2 Sec. 1.7.1)
\par Headers:
    time.h
\return byte count or 0 on error (errno not set)
*/
size_t strftime(
char *buf,  /**< output buffer*/
size_t bufsize, /**< size of buffer*/
const char *format, /**< format*/
const struct tm *tmbuf  /**< broken-down time*/
);
/**
\par Description:
Convert string to broken-down time with format
(Std. UNIX; see AUP2 Sec. 1.7.1)
\par Headers:
    time.h
\return ? or NULL on error (errno not set)
*/
char *strptime(
const char *s,  /**< string to convert*/
const char *format, /**< format*/
struct tm *tmbuf    /**< broken-down time (output)*/
);
/**
\par Description:
Structure for simple-semaphore functions
(Std. UNIX; see AUP2 Sec. 7.9.2)
\par Headers:
*/
struct SimpleSem {
    union {
        int sm_semid;/**< System V semaphore-set ID*/
        void *sm_sem;/**< POSIX sem_t pointer (needs a cast)*/
    } sm;
};
/**
\par Description:
Structure for getaddrinfo
(Std. UNIX; see AUP2 Sec. 8.2.6)
\par Headers:
*/
struct addrinfo {
int ai_flags;   /**< input flags*/
int ai_family;  /**< address family*/
int ai_socktype;    /**< socket type*/
int ai_protocol;    /**< protocol*/
socklen_t ai_addrlen;   /**< length of socket address*/
struct sockaddr *ai_addr;   /**< socket address*/
char *ai_canonname; /**< canonical name of service location*/
struct addrinfo *ai_next;   /**< pointer to next structure in list*/
};
/**
\par Description:
AIO control block
(Std. UNIX; see AUP2 Sec. 3.9.2)
\par Headers:
*/
struct aiocb {
int aio_fildes; /**< file descriptor*/
off_t aio_offset;   /**< file offset*/
volatile void *aio_buf; /**< buffer*/
size_t aio_nbytes;  /**< size of transfer*/
int aio_reqprio;    /**< request priority offset*/
struct sigevent aio_sigevent;   /**< signal information*/
int aio_lio_opcode; /**< operation to be performed*/
};
/**
\par Description:
Structure for readdir
(Std. UNIX; see AUP2 Sec. 3.6.1)
\par Headers:
*/
struct dirent {
ino_t d_ino;    /**< i-number*/
char d_name[];  /**< name*/
};
/**
\par Description:
Structure for fcntl file locking
(Std. UNIX; see AUP2 Sec. 7.11.4)
\par Headers:
*/
struct flock {
short l_type;   /**< lock type: F_RDLCK, F_WRLCK, F_UNLCK*/
short l_whence;     /**< interpretation of l_start*/
off_t l_start;  /**< start of section*/
off_t l_len;    /**< length of section*/
pid_t l_pid;    /**< process holding lock; used with F_GETLK*/
};
/**
\par Description:
Structure for getgrgid
(Std. UNIX; see AUP2 Sec. 3.5.2)
\par Headers:
*/
struct group {
char *gr_name;  /**< group name*/
gid_t gr_gid;   /**< group ID*/
char **gr_mem;  /**< member-name array (NULL terminated*/
};
/**
\par Description:
Structure for host-database functions
(Std. UNIX; see AUP2 Sec. 8.8.1)
\par Headers:
*/
struct hostent {
char *h_name;   /**< official host name*/
char **h_aliases;   /**< array of alternative host names*/
int h_addrtype; /**< address family (not type)*/
int h_length;   /**< length of each address*/
char **h_addr_list; /**< array of pointers to network addresses*/
};
/**
\par Description:
Structure for network-interface functions
(Std. UNIX; see AUP2 Sec. 8.8.5)
\par Headers:
*/
struct if_nameindex {
unsigned if_index;  /**< interface index*/
char *if_name;  /**< interface name*/
};
/**
\par Description:
Structure for readv and writev
(Std. UNIX; see AUP2 Sec. 2.15)
\par Headers:
*/
struct iovec {
    void *iov_base;/**< base address of data*/
    size_t iov_len;/**< size of this piece*/
};
/**
\par Description:
Structure for System V IPC permissions
(Std. UNIX; see AUP2 Sec. 7.4.3)
\par Headers:
*/
struct ipc_perm {
uid_t uid;  /**< owner user-ID*/
gid_t gid;  /**< owner group-ID*/
uid_t cuid; /**< creator user-ID*/
gid_t cgid; /**< creator group-ID*/
mode_t mode;    /**< permission bits*/
};
/**
\par Description:
Structure for timer_ functions
(Std. UNIX; see AUP2 Sec. 9.7.6)
\par Headers:
*/
struct itimerspec {
struct timespec it_interval;    /**< reset value*/
struct timespec it_value;   /**< current value*/
};
/**
\par Description:
Structure for getitimer and setitimer
(Std. UNIX; see AUP2 Sec. 9.7.4)
\par Headers:
*/
struct itimerval {
struct timeval it_interval; /**< reset value*/
struct timeval it_value;    /**< current value*/
};
/**
\par Description:
Structure for mq_open, mq_getattr, and mq_setattr
(Std. UNIX; see AUP2 Sec. 7.7.1)
\par Headers:
*/
struct mq_attr {
long mq_flags;  /**< flags*/
long mq_maxmsg; /**< max number of messages*/
long mq_msgsize;    /**< max message size*/
long mq_curmsgs;    /**< number of messages currently queued*/
};
/**
\par Description:
Typical structure for msgsnd and msgrcv
(Std. UNIX; see AUP2 Sec. 7.5.1)
\par Headers:
*/
struct msg {
    long mtype;/**< message type*/
    char mtext[MTEXTSIZE];/**< message text*/
};
/**
\par Description:
Structure for sendmsg and recvmsg
(Std. UNIX; see AUP2 Sec. 8.6.3)
\par Headers:
*/
struct msghdr {
void *msg_name; /**< optional address*/
socklen_t msg_namelen;  /**< size of address*/
struct iovec *msg_iov;  /**< scatter/gather array*/
int msg_iovlen; /**< number of elements in msg_iov*/
void *msg_control;  /**< ancillary data*/
socklen_t msg_controllen;   /**< ancillary data buffer len*/
int msg_flags;  /**< flags on received message*/
};
/**
\par Description:
Structure for msgctl
(Std. UNIX; see AUP2 Sec. 7.5.1)
\par Headers:
*/
struct msqid_ds {
struct ipc_perm msg_perm;   /**< permission structure*/
msgqnum_t msg_qnum; /**< number of messages currently on queue*/
msglen_t msg_qbytes;    /**< maximum number of bytes allowed on queue*/
pid_t msg_lspid;    /**< process ID of last msgsnd*/
pid_t msg_lrpid;    /**< process ID of last msgrcv*/
time_t msg_stime;   /**< time of last msgsnd*/
time_t msg_rtime;   /**< time of last msgrcv*/
time_t msg_ctime;   /**< time of last msgctl change*/
};
/**
\par Description:
Structure for network-database functions
(Std. UNIX; see AUP2 Sec. 8.8.2)
\par Headers:
*/
struct netent {
char *n_name;   /**< official network name*/
char **n_aliases;   /**< array of alternative network names*/
int n_addrtype; /**< address family (not type)*/
uint32_t n_net; /**< network number*/
};
/**
\par Description:
Structure for getpwuid
(Std. UNIX; see AUP2 Sec. 3.5.2)
\par Headers:
*/
struct passwd {
char *pw_name;  /**< login name*/
uid_t pw_uid;   /**< user ID*/
gid_t pw_gid;   /**< group ID*/
char *pw_dir;   /**< login directory*/
char *pw_shell;     /**< login shell*/
};
/**
\par Description:
Structure for poll
(Std. UNIX; see AUP2 Sec. 4.2.4)
\par Headers:
*/
struct pollfd {
int fd; /**< file descriptor*/
short events;   /**< input event flags (see table, below)*/
short revents;  /**< output event flags (see table, below)*/
};
/**
\par Description:
Structure for protocol-database functions
(Std. UNIX; see AUP2 Sec. 8.8.3)
\par Headers:
*/
struct protoent {
char *p_name;   /**< official protocol name*/
char **p_aliases;   /**< array of alternative protocol names*/
int p_proto;    /**< protocol number*/
};
/**
\par Description:
Structure for getrlimit and setrlimit
(Std. UNIX; see AUP2 Sec. 5.16)
\par Headers:
*/
struct rlimit {
rlim_t rlim_cur;    /**< current (soft) limit*/
rlim_t rlim_max;    /**< maximum (hard) limit*/
};
/**
\par Description:
Structure for getrusage
(Std. UNIX; see AUP2 Sec. 5.16)
\par Headers:
*/
struct rusage {
struct timeval ru_utime;    /**< user time used*/
struct timeval ru_stime;    /**< system time used*/
/**< following members are nonstandard*/
long ru_maxrss; /**< maximum resident set size*/
long ru_ixrss;  /**< integral shared memory size*/
long ru_idrss;  /**< integral unshared data size*/
long ru_isrss;  /**< integral unshared stack size*/
long ru_minflt; /**< page reclaims*/
long ru_majflt; /**< page faults*/
long ru_nswap;  /**< swaps*/
long ru_inblock;    /**< block input operations*/
long ru_oublock;    /**< block output operations*/
long ru_msgsnd; /**< messages sent*/
long ru_msgrcv; /**< messages received*/
long ru_nsignals;   /**< signals received*/
long ru_nvcsw;  /**< voluntary context switches*/
long ru_nivcsw; /**< involuntary context switches*/
};
/**
\par Description:
Structure for semop
(Std. UNIX; see AUP2 Sec. 7.9.2)
\par Headers:
*/
struct sembuf {
    unsigned short sem_num;/**< semaphore number*/
    short sem_op;/**< Semaphore operation*/
    short sem_flg;/**< Operation flags*/
};
/**
\par Description:
Structure for semctl
(Std. UNIX; see AUP2 Sec. 7.9.1)
\par Headers:
*/
struct semid_ds {
struct ipc_perm sem_perm;   /**< permission structure*/
unsigned short sem_nsems;   /**< size of set*/
time_t sem_otime;   /**< time of last semop*/
time_t sem_ctime;   /**< time of last semctl*/
};
/**
\par Description:
Structure for service-database functions
(Std. UNIX; see AUP2 Sec. 8.8.4)
\par Headers:
*/
struct servent {
char *s_name;   /**< official service name*/
char **s_aliases;   /**< array of alternative service names*/
int s_port; /**< port number*/
char *s_proto;  /**< name of protocol for this service*/
};
/**
\par Description:
Structure for sigaction
(Std. UNIX; see AUP2 Sec. 9.1.6)
\par Headers:
*/
struct sigaction {
void (*sa_handler)(int);    /**< SIG_DFL, SIG_IGN, or function pointer*/
sigset_t sa_mask;   /**< additional signals to be blocked */    int sa_flags;   /* flags*/
void (*sa_sigaction)(int, siginfo_t *, void *); /**< Realtime Signal handler*/
};
/**
\par Description:
Structure for RTS-generation functions
(Std. UNIX; see AUP2 Sec. 9.5.6)
\par Headers:
*/
struct sigevent {
int sigev_notify;   /**< notification type (see below)*/
int sigev_signo;    /**< signal number*/
union sigval sigev_value;   /**< signal value*/
void (*sigev_notify_function)(union sigval); /**< thread function*/
pthread_attr_t *sigev_notify_attributes;     /**< thread attributes*/
};
/**
\par Description:
Structure for AF_INET socket addresses
(Std. UNIX; see AUP2 Sec. 8.2.3)
<p>struct in_addr {
<br>in_addr_t s_addr        IPv4 address (uint32_t) 
<br>};
\par Headers:
    netinet/in.h
*/
struct sockaddr_in {
sa_family_t sin_family; /**< AF_INET*/
in_port_t sin_port; /**< port number (uint16_t)*/
struct in_addr sin_addr;    /**< IPv4 address*/
};
/**
\par Description:
Structure for AF_INET6 socket addresses
(Std. UNIX; see AUP2 Sec. 8.2.4)
<p>struct in6_addr {
<br>uint8_t s6_addr[16];        IPv6 address 
<br>};
\par Headers:
    netinet/in.h
*/
struct sockaddr_in6 {
sa_family_t sin6_family;    /**< AF_INET6*/
in_port_t sin6_port;    /**< port number (uint16_t)*/
uint32_t sin6_flowinfo; /**< traffic class and flow information*/
struct in6_addr sin6_addr;  /**< IPv4 address*/
uint32_t sin6_scope_id; /**< set of interfaces for a scope*/
};
/**
\par Description:
Structure for AF_UNIX socket addresses
(Std. UNIX; see AUP2 Sec. 8.2.2)
\par Headers:
    sys/un.h
*/
struct sockaddr_un {
sa_family_t sun_family; /**< AF_UNIX*/
char sun_path[X];   /**< socket pathname*/
};
/**
\par Description:
Structure for stat, fstat, and lstat
(Std. UNIX; see AUP2 Sec. 3.5.1)
\par Headers:
*/
struct stat {
dev_t st_dev;   /**< device ID of file system*/
ino_t st_ino;   /**< i-number*/
mode_t st_mode; /**< mode (see below).*/
nlink_t st_nlink;   /**< number of hard links*/
uid_t st_uid;   /**< user ID*/
gid_t st_gid;   /**< group ID*/
dev_t st_rdev;  /**< device ID (if special file).*/
off_t st_size;  /**< size in bytes*/
time_t st_atime;    /**< last access*/
time_t st_mtime;    /**< last data modification*/
time_t st_ctime;    /**< last i-node modification*/
blksize_t st_blksize;   /**< optimal I/O size*/
blkcnt_t st_blocks; /**< allocated 512-byte blocks*/
};
/**
\par Description:
Structure for statvfs and fstatvfs
(Std. UNIX; see AUP2 Sec. 3.2.3)
\par Headers:
*/
struct statvfs {
unsigned long f_bsize;  /**< block size*/
unsigned long f_frsize; /**< fundamental (fblock) size*/
fsblkcnt_t f_blocks;    /**< total number of fblocks*/
fsblkcnt_t f_bfree; /**< number of free fblocks*/
fsblkcnt_t f_bavail;    /**< number of avail. fblocks*/
fsfilcnt_t f_files; /**< total number of i-numbers*/
fsfilcnt_t f_ffree; /**< number of free i-numbers*/
fsfilcnt_t f_favail;    /**< number of avail. i-numbers*/
unsigned long f_fsid;   /**< file-system ID*/
unsigned long f_flag;   /**< flags (see below)*/
unsigned long f_namemax;    /**< max length of filename*/
};
/**
\par Description:
Structure for terminal-control functions
(Std. UNIX; see AUP2 Sec. 4.5.1)
\par Headers:
*/
struct termios {
tcflag_t c_iflag;   /**< input flags*/
tcflag_t c_oflag;   /**< output flags*/
tcflag_t c_cflag;   /**< control flags*/
tcflag_t c_lflag;   /**< local flags*/
cc_t c_cc[NCCS];    /**< control characters*/
};
/**
\par Description:
Structure for time in seconds and nanoseconds
(Std. UNIX; see AUP2 Sec. 1.7.2)
\par Headers:
*/
struct timespec {
time_t tv_sec;  /**< seconds*/
long tv_nsec;   /**< nanoseconds*/
};
/**
\par Description:
Structure for gettimeofday
(Std. UNIX; see AUP2 Sec. 1.7.1)
\par Headers:
*/
struct timeval {
time_t tv_sec;  /**< seconds*/
suseconds_t tv_usec;    /**< microseconds*/
};
/**
\par Description:
Structure for broken-down time
(Std. UNIX; see AUP2 Sec. 1.7.1)
\par Headers:
*/
struct tm {
int tm_sec; /**< second [0,60]*/
int tm_min; /**< minute [0,59]*/
int tm_hour;    /**< hour [0,23]*/
int tm_mday;    /**< day of month [1,31]*/
int tm_mon; /**< month  [0,11]*/
int tm_year;    /**< years since 1900*/
int tm_wday;    /**< day of week [0,6] (0 = Sunday)*/
int tm_yday;    /**< day of year [0,365]*/
int tm_isdst;   /**< daylight-savings flag*/
};
/**
\par Description:
Structure for times system call
(Std. UNIX; see AUP2 Sec. 1.7.2)
\par Headers:
*/
struct tms {
clock_t tms_utime;  /**< user time*/
clock_t tms_stime;  /**< sys time*/
clock_t tms_cutime; /**< user time of terminated children*/
clock_t tms_cstime; /**< sys time of terminated children*/
};
/**
\par Description:
Structure for utime
(Std. UNIX; see AUP2 Sec. 3.7.3)
\par Headers:
*/
struct utimbuf {
time_t actime;  /**< access time*/
time_t modtime; /**< modification time*/
};
/**
\par Description:
Create a symbolic link
(Std. UNIX; see AUP2 Sec. 3.3.3)
\par Headers:
    unistd.h
\return 0 on success or -1 on error (sets errno)
*/
int symlink(
const char *oldpath,    /**< old pathname*/
const char *newpath /**< possible new pathname*/
);
/**
\par Description:
Schedule buffer-cache flushing
(Std. UNIX; see AUP2 Sec. 2.16.2)
\par Headers:
    unistd.h
*/
void sync(void);
/**
\par Description:
Get system option or limit
(Std. UNIX; see AUP2 Sec. 1.5.5)
\par Headers:
    unistd.h
\return option/limit value or -1 (sets errno on error)
*/
long sysconf(
int name    /**< option or limit name*/
);
/**
\par Description:
Run command
(Std. UNIX; see AUP2 Sec. 5.5)
\par Headers:
    stdlib.h
\return exit status or -1 on error (sets errno)
*/
int system(
const char *command /**< command*/
);
/**
\par Description:
Drain (wait for) terminal output
(Std. UNIX; see AUP2 Sec. 4.6)
\par Headers:
    termios.h
\return 0 on success or -1 on error (sets errno)
*/
int tcdrain(
int fd  /**< file descriptor*/
);
/**
\par Description:
Suspend or restart flow of terminal input or output
(Std. UNIX; see AUP2 Sec. 4.6)
\par Headers:
    termios.h
\return 0 on success or -1 on error (sets errno)
*/
int tcflow(
int fd, /**< file descriptor*/
int action  /**< direction and suspend/restart*/
);
/**
\par Description:
Flush (throw away) terminal output, input, or both
(Std. UNIX; see AUP2 Sec. 4.6)
\par Headers:
    termios.h
\return 0 on success or -1 on error (sets errno)
*/
int tcflush(
int fd, /**< file descriptor*/
int queue   /**< queue to be affected*/
);
/**
\par Description:
Get terminal attributes
(Std. UNIX; see AUP2 Sec. 4.5.1)
\par Headers:
    termios.h
\return 0 on success or -1 on error (sets errno)
*/
int tcgetattr(
int fd, /**< file descriptor*/
struct termios *tp  /**< attributes*/
);
/**
\par Description:
Get foreground process-group ID
(Std. UNIX; see AUP2 Sec. 4.3.4)
\par Headers:
    unistd.h
\return process-group ID or -1 on error (sets errno)
*/
pid_t tcgetpgrp(
int fd  /**< file descriptor*/
);
/**
\par Description:
Get session ID
(Std. UNIX; see AUP2 Sec. 4.3.4)
\par Headers:
    termios.h
\return session ID or -1 on error (sets errno)
*/
pid_t tcgetsid(
int fd  /**< file descriptor*/
);
/**
\par Description:
Send break to terminal
(Std. UNIX; see AUP2 Sec. 4.6)
\par Headers:
    termios.h
\return 0 on success or -1 on error (sets errno)
*/
int tcsendbreak(
int fd, /**< file descriptor*/
int duration    /**< duration of break*/
);
/**
\par Description:
Set terminal attributes
(Std. UNIX; see AUP2 Sec. 4.5.1)
\par Headers:
    termios.h
\return 0 on success or -1 on error (sets errno)
*/
int tcsetattr(
int fd, /**< file descriptor*/
int actions,    /**< actions on setting*/
const struct termios *tp    /**< attributes*/
);
/**
\par Description:
Set foreground process-group ID
(Std. UNIX; see AUP2 Sec. 4.3.4)
\par Headers:
    unistd.h
\return 0 on success or -1 on error (sets errno)
*/
int tcsetpgrp(
int fd, /**< file descriptor*/
pid_t pgid  /**< process-group ID*/
);
/**
\par Description:
Get directory location
(Std. UNIX; see AUP2 Sec. 3.6.1)
\par Headers:
    dirent.h
\return location (no error return)
*/
long telldir(
DIR *dirp   /**< DIR pointer from opendir*/
);
/**
\par Description:
Get current date and time as time_t
(Std. UNIX; see AUP2 Sec. 1.7.1)
\par Headers:
    time.h
\return time or -1 on error (errno not set)
*/
time_t time(
time_t *t   /**< NULL or returned time*/
);
/**
\par Description:
Create per-process timer
(Std. UNIX; see AUP2 Sec. 9.7.6)
\par Headers:
    signal.h
    , time.h
\return 0 on success or -1 on error (sets errno)
*/
int timer_create(
clockid_t clockid,  /**< clock ID*/
struct sigevent *sig,   /**< NULL or signal to generate*/
timer_t *timer_id   /**< returned timer ID*/
);
/**
\par Description:
Delete per-process timer
(Std. UNIX; see AUP2 Sec. 9.7.6)
\par Headers:
    time.h
\return 0 on success or -1 on error (sets errno)
*/
int timer_delete(
timer_t timer_id    /**< timer ID*/
);
/**
\par Description:
Get per-process timer overrun count
(Std. UNIX; see AUP2 Sec. 9.7.6)
\par Headers:
    time.h
\return overrun count  or -1 on error (sets errno)
*/
int timer_getoverrun(
timer_t timer_id    /**< timer ID*/
);
/**
\par Description:
Get value of per-process timer
(Std. UNIX; see AUP2 Sec. 9.7.6)
\par Headers:
    time.h
\return 0 on success or -1 on error (sets errno)
*/
int timer_gettime(
timer_t timer_id,   /**< timer ID*/
struct itimerspec *val  /**< returned value*/
);
/**
\par Description:
Set value of per-process timer
(Std. UNIX; see AUP2 Sec. 9.7.6)
\par Headers:
    time.h
\return 0 on success or -1 on error (sets errno)
*/
int timer_settime(
timer_t timer_id,   /**< timer ID*/
int flags,  /**< flags*/
const struct itimerspec *val,   /**< value to set*/
struct itimerspec *oval /**< returned old value*/
);
/**
\par Description:
Get process and child-process execution times
(Std. UNIX; see AUP2 Sec. 1.7.2)
\par Headers:
    sys/times.h
\return time in clock ticks or -1 on error (sets errno)
*/
clock_t times(
struct tms *buffer  /**< */
);
/**
\par Description:
Truncate or stretch file by path
(Std. UNIX; see AUP2 Sec. 2.17)
\par Headers:
    unistd.h
\return 0 on success or -1 on error (sets errno)
*/
int truncate(
const char *path,   /**< pathname*/
off_t length    /**< new length*/
);
/**
\par Description:
Find pathname of terminal
(Std. UNIX; see AUP2 Sec. 4.7)
\par Headers:
    unistd.h
\return string or NULL on error (sets errno)
*/
char *ttyname(
int fd  /**< file descriptor*/
);
/**
\par Description:
Find pathname of terminal
(Std. UNIX; see AUP2 Sec. 4.7)
\par Headers:
    unistd.h
\return 0 on success or error number on error (sets errno)
*/
int ttyname_r(
int fd, /**< file descriptor*/
char *buf,  /**< buffer for pathname*/
size_t bufsize  /**< size of buffer*/
);
/**
\par Description:
Set time zone information
(Std. UNIX; see AUP2 Sec. 1.7.1)
\par Headers:
    time.h
*/
extern int daylight;/**< DST? (not in FreeBSD)*/
extern long timezone; /**< timezone in secs (not in FreeBSD)*/
extern char *tzname[2]; /**< timezone strings (not in FreeBSD)*/
void tzset(void);
/**
\par Description:
Get and set process limits
(Std. UNIX; see AUP2 Sec. 5.16)
\par Headers:
    ulimit.h
\return limit or -1 with errno changed on error (sets errno)
*/
long ulimit(
int cmd,    /**< command*/
... /**< optional argument*/
);
/**
\par Description:
Set and get file mode creation mask
(Std. UNIX; see AUP2 Sec. 2.5)
\par Headers:
    sys/stat.h
\return previous mask (no error return)
*/
mode_t umask(
mode_t cmask    /**< new mask*/
);
/**
\par Description:
Unmount file system (non-standard)
(Std. UNIX; see AUP2 Sec. 3.2.4)
\par Headers:
    sys/mount.h
\return 0 on success or -1 on error (sets errno)
*/
int umount(
const char *target  /**< directory*/
);
/**
\par Description:
Get the name of the current system
(Std. UNIX; see AUP2 Sec. 8.8.1)
\par Headers:
    sys/utsname.h
\return ? or -1 on error (sets errno)
*/
int uname(
struct utsname *name    /**< */
);
/**
\par Description:
Union for semctl
(Std. UNIX; see AUP2 Sec. 7.9.1)
\par Headers:
*/
union semun {
    int val;/**< integer*/
    struct semid_ds *buf;/**< pointer to structure*/
    unsigned short *array;/**< array*/
};
/**
\par Description:
Union for signal values
(Std. UNIX; see AUP2 Sec. 9.5.1)
\par Headers:
*/
union sigval {
int sival_int;  /**< Integer signal value*/
void *sival_ptr;    /**< Pointer signal value*/
};
/**
\par Description:
Remove directory entry
(Std. UNIX; see AUP2 Sec. 2.6)
\par Headers:
    unistd.h
\return 0 on success or -1 on error (sets errno)
*/
int unlink(
const char *path    /**< pathname*/
);
/**
\par Description:
Unlock pty
(Std. UNIX; see AUP2 Sec. 4.10.1)
\par Headers:
    stdlib.h
\return 0 on success or -1 on error (sets errno)
*/
int unlockpt(
int fd  /**< file descriptor*/
);
/**
\par Description:
Remove environment variable
(Std. UNIX; see AUP2 Sec. 5.2)
\par Headers:
    stdlib.h
\return 0 on success or -1 on error (sets errno)
*/
int unsetenv(
const char *var /**< variable to be removed*/
);
/**
\par Description:
Suspend execution for microseconds or until signal
(Std. UNIX; see AUP2 Sec. 9.7.3)
\par Headers:
    unistd.h
\return 0 on success or -1 on error (sets errno)
*/
int usleep(
useconds_t usecs    /**< microseconds to sleep*/
);
/**
\par Description:
Set file access and modification times
(Std. UNIX; see AUP2 Sec. 3.7.3)
\par Headers:
    utime.h
\return 0 on success or -1 on error (sets errno)
*/
int utime(
const char *path,   /**< pathname*/
const struct utimbuf *timbuf    /**< new times*/
);
/**
\par Description:
Create new process; share memory (obsolete)
(Std. UNIX; see AUP2 Sec. 5.5)
\par Headers:
    unistd.h
\return child’s process-ID and 0 on success or -1 on error (sets errno)
*/
pid_t vfork(void);
/**
\par Description:
Wait for child process to terminate
(Std. UNIX; see AUP2 Sec. 5.8)
\par Headers:
    sys/wait.h
\return process ID or -1 on error (sets errno)
*/
pid_t wait(
int *statusp,   /**< pointer to status or NULL*/
);
/**
\par Description:
Wait for child process to change state [X/Open]
(Std. UNIX; see AUP2 Sec. 5.8)
\par Headers:
    sys/wait.h
\return 0 on success or -1 on error (sets errno)
*/
int waitid(
idtype_t idtype,    /**< interpretation of id*/
id_t id,    /**< process or process-group ID*/
siginfo_t *infop,   /**< returned info*/
int options /**< options*/
);
/**
\par Description:
Wait for child process to change state
(Std. UNIX; see AUP2 Sec. 5.8)
\par Headers:
    sys/wait.h
\return process ID or 0 on success or -1 on error (sets errno)
*/
pid_t waitpid(
pid_t pid,  /**< process or process-group ID*/
int *statusp,   /**< pointer to status or NULL*/
int options /**< options (see below)*/
);
/**
\par Description:
Convert broken-down time to wide-character string with format
(Std. UNIX; see AUP2 Sec. 1.7.1)
\par Headers:
    wchar.h
\return wchar_t count or zero on error (errno not set)
*/
size_t wcsftime(
wchar_t *buf,   /**< output buffer*/
size_t bufsize,     /**< size of buffer*/
const wchar_t *format,  /**< format*/
const struct tm *tmbuf  /**< broken-down time*/
);
/**
\par Description:
Write to file descriptor
(Std. UNIX; see AUP2 Sec. 2.9)
\par Headers:
    unistd.h
\return number of bytes written or -1 on error (sets errno)
*/
ssize_t write(
int fd, /**< file descriptor*/
const void *buf,    /**< data to write*/
size_t nbytes   /**< amount to write*/
);
/**
\par Description:
Gather write
(Std. UNIX; see AUP2 Sec. 2.15)
\par Headers:
    sys/uio.h
\return number of bytes written or -1 on error (sets errno)
*/
ssize_t writev(
int fd, /**< file descriptor*/
const struct iovec *iov,    /**< vector of data buffers*/
int iovcnt  /**< number of elements*/
);

---