docs: update isatty documentation to refer to terminals

Use language that is more accurate, similar to what glibc uses.

Closes #6355.
This commit is contained in:
David Adam 2019-11-26 18:18:16 +08:00
parent b8a9f2f228
commit 563bdf3cc7

View file

@ -1,7 +1,7 @@
.. _cmd-isatty:
isatty - test if a file descriptor is a tty.
============================================
isatty - test if a file descriptor is a terminal
================================================
Synopsis
--------
@ -13,11 +13,11 @@ Synopsis
Description
-----------
``isatty`` tests if a file descriptor is a tty.
``isatty`` tests if a file descriptor is a terminal (as opposed to a file). The name is derived from the system call of the same name, which for historical reasons refers to a teletypewriter (TTY).
``FILE DESCRIPTOR`` may be either the number of a file descriptor, or one of the strings ``stdin``, ``stdout``, or ``stderr``.
If the specified file descriptor is a tty, the exit status of the command is zero. Otherwise, the exit status is non-zero. No messages are printed to standard error.
If the specified file descriptor is a terminal device, the exit status of the command is zero. Otherwise, the exit status is non-zero. No messages are printed to standard error.
Examples