# PXFISATTY (L*X, M*X)

POSIX Subroutine: Tests whether a file descriptor is connected to a terminal.

## Module

USE IFPOSIX

CALL PXFISATTY (ifildes,isatty,ierror)

ifildes | (Input) INTEGER(4). The file descriptor.
isatty | (Output) LOGICAL(4). The returned value.
ierror | (Output) INTEGER(4). The error status.

If successful, ierror is set to zero; otherwise, an error code.

If file descriptor ifildes is open and connected to a terminal, isatty returns .TRUE.; otherwise, .FALSE..

Parent topic: POSIX* Library Routines

## See Also

PXFOPEN