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From: Alexis <flexibeast@gmail.com>
Newsgroups: comp.lang.c
Subject: Re: Can 'graphics' be a file descriptor?
Date: Thu, 02 Jan 2025 10:22:28 +1100
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Keith Thompson <Keith.S.Thompson+u@gmail.com> writes:

> Why do you insist on referring to "file descriptors"?  That's a specific
> term with a specific meaning: a small integer value used in POSIX I/O
> (not in standard C).

Indeed; cf. https://pubs.opengroup.org/onlinepubs/9799919799/basedefs/V1_chap03.html#tag_03_141:

> 3.141 File Descriptor
> 
> A per-process unique, non-negative integer used to identify an open
> file for the purpose of file access. The values 0, 1, and 2 have
> special meaning and conventional uses, and are referred to as standard
> input, standard output, and standard error, respectively. Programs
> usually take their input from standard input, and write output on
> standard output. Diagnostic messages are usually written on standard
> error. The value of a newly-created file descriptor is from zero to
> {OPEN_MAX}-1. A file descriptor can have a value greater than or equal
> to {OPEN_MAX} if the value of {OPEN_MAX} has decreased (see sysconf)
> since the file descriptor was opened. File descriptors may also be
> used to implement message catalog descriptors and directory streams;
> see also 3.241 Open File Description. 


Alexis.