explain_fileno_or_die(3)

💖 explain_fileno_or_die — the libexplain glow-up of fileno(3) 💖

okay bestie, so this one lives in the Library Functions Manual and it's called explain_fileno_or_die(3) — and no cap, the name tells you everything: it's fileno(3) but with ✨feelings✨ and also it might end your whole process. iconique behaviour, honestly.

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✨ NAME ✨

explain_fileno_or_die — check and reset stream status and report errors

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🌸 SYNOPSIS 🌸

#include <libexplain/fileno.h>
int explain_fileno_or_die(FILE *fp);
int explain_fileno_on_error(FILE *fp);

like. two functions. two vibes. one header. we love a duo 🫶

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🎀 DESCRIPTION 🎀

okay so the way this works is:

• explain_fileno_or_die is the function you call when you wanna call the fileno(3) system call. and if it fails? an explanation gets printed to stderr, which it gets from the explain_fileno(3) function, and then the process terminates by calling exit(EXIT_FAILURE). yeah. it's giving "we're not doing this today". 💀
• explain_fileno_on_error is the softer sister. she also calls the fileno(3) system call, and on failure she also prints an explanation to stderr (again, obtained from the explain_fileno(3) function), BUT she still returns to the caller. she's the friend who walks you home instead of just leaving. 🌈

and then the argument:

• fp — the fp, exactly as to be passed to the fileno(3) system call. literally just hand it over the same way, don't get creative, bestie. ✨

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💅 RETURN VALUE 💅

explain_fileno_or_die only returns on success — peep fileno(3) for more info on that. on failure? it prints an explanation and exits. it does not return. like, at all. it's gone. 👑

explain_fileno_on_error always returns the value returned by the wrapped fileno(3) system call. always. every time. that's her whole thing. 💖

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🦋 EXAMPLE 🦋

the explain_fileno_or_die function is intended to be used in a fashion similar to the following example:

explain_fileno_or_die(fp);

that's it. that's the example. short, sweet, ate. 🔥

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👑 SEE ALSO 👑

• fileno(3) — check and reset stream status
• explain_fileno(3) — explain fileno(3) errors
• exit(2) — terminate the calling process

iykyk, the whole little family is here. 🧚

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💜 COPYRIGHT 💜

libexplain version 1.4 Copyright (C) 2009 Peter Miller

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and that's the page, bestie — coming at you from the Library Functions Manual, libexplain version 1.4 era, with copyright belonging to Peter Miller since 2009. periodt. 💅✨