POSIX* Library Routines

This section contains descriptions of the POSIX* library routines. They are listed in alphabetical order.

To access the POSIX library, you must specify a USE IFPOSIX statement in your program.

Certain POSIX* routines are restricted to Linux* and macOS* systems. If a routine is restricted, it will show labels "(L*X, M*X)" in the routine title.

• IPXFARGC
  POSIX Function: Returns the index of the last command-line argument.
• IPXFCONST
  POSIX Function: Returns the value associated with a constant defined in the C POSIX standard.
• IPXFLENTRIM
  POSIX Function: Returns the index of the last non-blank character in an input string.
• IPXFWEXITSTATUS (L*X, M*X)
  POSIX Function: Returns the exit code of a child process.
• IPXFWSTOPSIG (L*X, M*X)
  POSIX Function: Returns the number of the signal that caused a child process to stop.
• IPXFWTERMSIG (L*X, M*X)
  POSIX Function: Returns the number of the signal that caused a child process to terminate.
• PXF(type)GET
  POSIX Subroutine: Gets the value stored in a component (or field) of a structure.
• PXF(type)SET
  POSIX Subroutine: Sets the value of a component (or field) of a structure.
• PXFA(type)GET
  POSIX Subroutine: Gets the array values stored in a component (or field) of a structure.
• PXFA(type)SET
  POSIX Subroutine: Sets the value of an array component (or field) of a structure.
• PXFACCESS
  POSIX Subroutine: Determines the accessibility of a file.
• PXFALARM
  POSIX Subroutine: Schedules an alarm.
• PXFCALLSUBHANDLE
  POSIX Subroutine: Calls the associated subroutine.
• PXFCFGETISPEED (L*X, M*X)
  POSIX Subroutine: Returns the input baud rate from a termios structure.
• PXFCFGETOSPEED (L*X, M*X)
  POSIX Subroutine: Returns the output baud rate from a termios structure.
• PXFCFSETISPEED (L*X, M*X)
  POSIX Subroutine: Sets the input baud rate in a termios structure.
• PXFCFSETOSPEED (L*X, M*X)
  POSIX Subroutine: Sets the output baud rate in a termios structure.
• PXFCHDIR
  POSIX Subroutine: Changes the current working directory.
• PXFCHMOD
  POSIX Subroutine: Changes the ownership mode of the file.
• PXFCHOWN (L*X, M*X)
  POSIX Subroutine: Changes the owner and group of a file.
• PXFCLEARENV
  POSIX Subroutine: Clears the process environment.
• PXFCLOSE
  POSIX Subroutine: Closes the file associated with the descriptor.
• PXFCLOSEDIR
  POSIX Subroutine: Closes the directory stream.
• PXFCONST
  POSIX Subroutine: Returns the value associated with a constant.
• PXFCREAT
  POSIX Subroutine: Creates a new file or rewrites an existing file.
• PXFCTERMID (L*X, M*X)
  POSIX Subroutine: Generates a terminal pathname.
• PXFDUP, PXFDUP2
  POSIX Subroutine: Duplicates an existing file descriptor.
• PXFE(type)GET
  POSIX Subroutine: Gets the value stored in an array element component (or field) of a structure.
• PXFE(type)SET
  POSIX Subroutine: Sets the value of an array element component (or field) of a structure.
• PXFEXECV
  POSIX Subroutine: Executes a new process by passing command-line arguments.
• PXFEXECVE
  POSIX Subroutine: Executes a new process by passing command-line arguments.
• PXFEXECVP
  POSIX Subroutine: Executes a new process by passing command-line arguments.
• PXFEXIT, PXFFASTEXIT
  POSIX Subroutine: Exits from a process.
• PXFFCNTL (L*X, M*X)
  POSIX Subroutine: Manipulates an open file descriptor.
• PXFFDOPEN
  POSIX Subroutine: Opens an external unit.
• PXFFFLUSH
  POSIX Subroutine: Flushes a file directly to disk.
• PXFFGETC
  POSIX Subroutine: Reads a character from a file.
• PXFFILENO
  POSIX Subroutine: Returns the file descriptor associated with a specified unit.
• PXFFORK (L*X, M*X)
  POSIX Subroutine: Creates a child process that differs from the parent process only in its PID.
• PXFFPATHCONF
  POSIX Subroutine: Gets the value for a configuration option of an opened file.
• PXFFPUTC
  POSIX Subroutine: Writes a character to a file.
• PXFFSEEK
  POSIX Subroutine: Modifies a file position.
• PXFFSTAT
  POSIX Subroutine: Gets a file's status information.
• PXFFTELL
  POSIX Subroutine: Returns the relative position in bytes from the beginning of the file.
• PXFGETARG
  POSIX Subroutine: Gets the specified command-line argument.
• PXFGETC
  POSIX Subroutine: Reads a character from standard input unit 5.
• PXFGETCWD
  POSIX Subroutine: Returns the path of the current working directory.
• PXFGETEGID (L*X, M*X)
  POSIX Subroutine: Gets the effective group ID of the current process.
• PXFGETENV
  POSIX Subroutine: Gets the setting of an environment variable.
• PXFGETEUID (L*X, M*X)
  POSIX Subroutine: Gets the effective user ID of the current process.
• PXFGETGID (L*X, M*X)
  POSIX Subroutine: Gets the real group ID of the current process.
• PXFGETGRGID (L*X, M*X)
  POSIX Subroutine: Gets group information for the specified GID.
• PXFGETGRNAM (L*X, M*X)
  POSIX Subroutine: Gets group information for the named group.
• PXFGETGROUPS (L*X, M*X)
  POSIX Subroutine: Gets supplementary group IDs.
• PXFGETLOGIN
  POSIX Subroutine: Gets the name of the user.
• PXFGETPGRP (L*X, M*X)
  POSIX Subroutine: Gets the process group ID of the calling process.
• PXFGETPID
  POSIX Subroutine: Gets the process ID of the calling process.
• PXFGETPPID
  POSIX Subroutine: Gets the process ID of the parent of the calling process.
• PXFGETPWNAM (L*X, M*X)
  POSIX Subroutine: Gets password information for a specified name.
• PXFGETPWUID (L*X, M*X)
  POSIX Subroutine: Gets password information for a specified UID.
• PXFGETSUBHANDLE
  POSIX Subroutine: Returns a handle for a subroutine.
• PXFGETUID (L*X, M*X)
  POSIX Subroutine: Gets the real user ID of the current process.
• PXFISATTY (L*X, M*X)
  POSIX Subroutine: Tests whether a file descriptor is connected to a terminal.
• PXFISBLK
  POSIX Function: Tests for a block special file.
• PXFISCHR
  POSIX Function: Tests for a character file.
• PXFISCONST
  POSIX Function: Tests whether a string is a valid constant name.
• PXFISDIR
  POSIX Function: Tests whether a file is a directory.
• PXFISFIFO
  POSIX Function: Tests whether a file is a special FIFO file.
• PXFISREG
  POSIX Function: Tests whether a file is a regular file.
• PXFKILL
  POSIX Subroutine: Sends a signal to a specified process.
• PXFLINK (L*X, M*X)
  POSIX Subroutine: Creates a link to a file or a directory.
• PXFLOCALTIME
  POSIX Subroutine: Converts a given elapsed time in seconds to local time.
• PXFLSEEK
  POSIX Subroutine: Positions a file a specified distance in bytes.
• PXFMKDIR
  POSIX Subroutine: Creates a new directory.
• PXFMKFIFO (L*X, M*X)
  POSIX Subroutine: Creates a new FIFO.
• PXFOPEN
  POSIX Subroutine: Opens or creates a file.
• PXFOPENDIR
  POSIX Subroutine: Opens a directory and associates a stream with it.
• PXFPATHCONF
  POSIX Subroutine: Gets the value for a configuration option of an opened file.
• PXFPAUSE
  POSIX Subroutine: Suspends process execution.
• PXFPIPE (L*X, M*X)
  POSIX Subroutine: Creates a communications pipe between two processes.
• PXFPOSIXIO
  POSIX Subroutine: Sets the current value of the POSIX I/O flag.
• PXFPUTC
  POSIX Subroutine: Outputs a character to logical unit 6 (stdout).
• PXFREAD
  POSIX Subroutine: Reads from a file.
• PXFREADDIR
  POSIX Subroutine: Reads the current directory entry.
• PXFRENAME
  POSIX Subroutine: Changes the name of a file.
• PXFREWINDDIR
  POSIX Subroutine: Resets the position of the stream to the beginning of the directory.
• PXFRMDIR
  POSIX Subroutine: Removes a directory.
• PXFSETENV
  POSIX Subroutine: Adds a new environment variable or sets the value of an environment variable.
• PXFSETGID (L*X, M*X)
  POSIX Subroutine: Sets the effective group ID of the current process.
• PXFSETPGID (L*X, M*X)
  POSIX Subroutine: Sets the process group ID.
• PXFSETSID (L*X, M*X)
  POSIX Subroutine: Creates a session and sets the process group ID.
• PXFSETUID (L*X, M*X)
  POSIX Subroutine: Sets the effective user ID of the current process.
• PXFSIGACTION (L*X, M*X)
  POSIX Subroutine: Changes the action associated with a specific signal. It can also be used to examine the action of a signal.
• PXFSIGADDSET (L*X, M*X)
  POSIX Subroutine: Adds a signal to the signal set.
• PXFSIGDELSET (L*X, M*X)
  POSIX Subroutine: Deletes a signal from the signal set.
• PXFSIGEMPTYSET (L*X, M*X)
  POSIX Subroutine: Empties a signal set.
• PXFSIGFILLSET (L*X, M*X)
  POSIX Subroutine: Fills a signal set.
• PXFSIGISMEMBER (L*X, M*X)
  POSIX Subroutine: Tests whether a signal is a member of a signal set.
• PXFSIGPENDING (L*X, M*X)
  POSIX Subroutine: Examines pending signals.
• PXFSIGPROCMASK (L*X, M*X)
  POSIX Subroutine: Changes the list of currently blocked signals.
• PXFSIGSUSPEND (L*X, M*X)
  POSIX Subroutine: Suspends the process until a signal is received.
• PXFSLEEP
  POSIX Subroutine: Forces the process to sleep.
• PXFSTAT
  POSIX Subroutine: Gets a file's status information.
• PXFSTRUCTCOPY
  POSIX Subroutine: Copies the contents of one structure to another.
• PXFSTRUCTCREATE
  POSIX Subroutine: Creates an instance of the specified structure.
• PXFSTRUCTFREE
  POSIX Subroutine: Deletes the instance of a structure.
• PXFSYSCONF
  POSIX Subroutine: Gets values for system limits or options.
• PXFTCDRAIN (L*X, M*X)
  POSIX Subroutine: Waits until all output written has been transmitted.
• PXFTCFLOW (L*X, M*X)
  POSIX Subroutine: Suspends the transmission or reception of data.
• PXFTCFLUSH (L*X, M*X)
  POSIX Subroutine: Discards terminal input data, output data, or both.
• PXFTCGETATTR (L*X, M*X)
  POSIX Subroutine: Reads current terminal settings.
• PXFTCGETPGRP (L*X, M*X)
  POSIX Subroutine: Gets the foreground process group ID associated with the terminal.
• PXFTCSENDBREAK (L*X, M*X)
  POSIX Subroutine: Sends a break to the terminal.
• PXFTCSETATTR (L*X, M*X)
  POSIX Subroutine: Writes new terminal settings.
• PXFTCSETPGRP (L*X, M*X)
  POSIX Subroutine: Sets the foreground process group ID associated with the terminal.
• PXFTIME
  POSIX Subroutine: Returns the current system time.
• PXFTIMES
  POSIX Subroutine: Returns process times.
• PXFTTYNAME (L*X, M*X)
  POSIX Subroutine: Gets the terminal pathname.
• PXFUCOMPARE
  POSIX Subroutine: Compares two unsigned integers.
• PXFUMASK
  POSIX Subroutine: Sets a new file creation mask and gets the previous one.
• PXFUNAME
  POSIX Subroutine: Gets the operation system name.
• PXFUNLINK
  POSIX Subroutine: Removes a directory entry.
• PXFUTIME
  POSIX Subroutine: Sets file access and modification times.
• PXFWAIT (L*X, M*X)
  POSIX Subroutine: Waits for a child process.
• PXFWAITPID (L*X, M*X)
  POSIX Subroutine: Waits for a specific PID.
• PXFWIFEXITED (L*X, M*X)
  POSIX Function: Determines if a child process has exited.
• PXFWIFSIGNALED (L*X, M*X)
  POSIX Function: Determines if a child process has exited because of a signal.
• PXFWIFSTOPPED (L*X, M*X)
  POSIX Function: Determines if a child process has stopped.
• PXFWRITE
  POSIX Subroutine: Writes to a file.