explain_ftell_or_die(3)

✨ explain_ftell_or_die — the ftell(3) glow-up bestie 💖

okay so this is explain_ftell_or_die(3), from the Library Functions Manual, and it's genuinely one of my faves because it does the exact thing you already wanted ftell(3) to do, but with ✨consequences✨. no cap.

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🌸 SYNOPSIS 🌸

#include <libexplain/ftell.h>
long explain_ftell_or_die(FILE *fp);
long explain_ftell_on_error(FILE *fp);

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💅 DESCRIPTION 💅

so there are two functions here and they're siblings, not twins. let's get into it 🫶

• explain_ftell_or_die — this one calls the ftell(3) system call for you. and if it fails? bestie, it prints an explanation to stderr (which it gets from the explain_ftell(3) function, iconic) and then the process terminates by calling exit(EXIT_FAILURE). that's the "or die" part. she's dramatic and she means it. 💀
• explain_ftell_on_error — same deal, calls the ftell(3) system call, and on failure it also prints an explanation to stderr, also obtained from the explain_ftell(3) function. BUT. she still returns to the caller. no exit, no drama, just the tea and a return value. 🌈

fp — the fp, exactly as to be passed to the ftell(3) system call. like, literally, don't get creative with it, just hand it over as-is. 💜

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⭐ RETURN VALUE ⭐

explain_ftell_or_die only returns on success — peep ftell(3) for more info on that. on failure it prints an explanation and exits, so it does not return. she said "I'm leaving" and she left. 🎀

explain_ftell_on_error always returns the value return by the wrapped ftell(3) system call. always. every time. 💫

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🦋 EXAMPLE 🦋

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

long result = explain_ftell_or_die(fp);

that's it. that's the whole vibe. 👑

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🔥 SEE ALSO 🔥

• ftell(3) — get stream position
• explain_ftell(3) — explain ftell(3) errors
• exit(2) — terminate the calling process

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👑 COPYRIGHT 👑

libexplain version 1.4

Copyright (C) 2010 Peter Miller

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okay that's the whole page, bestie, you're officially fluent in explain_ftell_or_die(3) 💖 go forth and never wonder why your ftell returned -1 ever again. mwah. 🎀✨🦋

libexplain version 1.4 🌸 Copyright (C) 2010 Peter Miller — that's the source, the version and the date, all wrapped up with a bow, ty for coming to my ted talk 🫶💜