ISASTREAM(3P)

💖 ISASTREAM(3P) — the POSIX Programmer's Manual, but make it make sense 💖

okay bestie, gather round, because we're doing isastream(3P) and it's giving niche but iconic ✨

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🫶 PROLOG

So here's the tea: this manual page is part of the POSIX Programmer's Manual. The Linux implementation of this interface may differ — so if you're on Linux, go consult the corresponding Linux manual page for the details of Linux behavior. Or, plot twist, the interface may not be implemented on Linux at all. 😭 Not to be dramatic but that's a real possibility.

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✨ NAME

isastream — test a file descriptor (STREAMS)

Like. That's it. That's the whole job. It checks a file descriptor and tells you if it's STREAMS-coded. 💅

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🌸 SYNOPSIS

#include <stropts.h>

int isastream(int fildes);

There it is. One include, one function, one int going in, one int coming out. Clean. Minimalist. Main character energy fr fr.

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🦋 DESCRIPTION

So isastream() shall test whether fildes — that's an open file descriptor — is associated with a STREAMS-based file.

That's the vibe check. It's not opening anything, it's not changing anything, it's just ✨ looking ✨. iykyk.

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👑 RETURN VALUE

Okay so here's the scoring system, and it's lowkey simple:

• Upon successful completion, isastream() shall return 1 if fildes refers to a STREAMS-based file. 💖
• It shall return 0 if not. 🙈
• Otherwise, isastream() shall return -1 and set errno to indicate the error. 💀

Not me memorising this like it's a pop quiz. 1 yes, 0 no, -1 something went wrong bestie.

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🔥 ERRORS

The isastream() function shall fail if:

• EBADF — The fildes argument is not a valid open file descriptor.

And that's the whole list. One error. It said "I have exactly one problem and it's you not giving me a real file descriptor." 😤

Heads up: the following sections are informative. (So like, they're context, not requirements. The standard said "this part is just chatting." 💅)

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🌈 EXAMPLES

None.

Yeah. Nothing. Empty. The void. The audacity. 😭

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🍓 APPLICATION USAGE

None.

Also nothing!! Two empty sections back to back, it's giving "the standard was on a deadline." periodt.

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🧚 RATIONALE

None.

Three for three, bestie. Truly nothing to explain here.

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⭐ FUTURE DIRECTIONS

The isastream() function may be removed in a future version.

NOT THE DEPRECATION NOTICE 😭 so like, use it if you need it, but don't get too attached. It might not be here forever. Keep that in mind. 🫶

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💜 SEE ALSO

• The Base Definitions volume of POSIX.1‐2017, <stropts.h>

That's your one and only reference. Go read the header. Slay.

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🎀 COPYRIGHT

Portions of this text are reprinted and reproduced in electronic form from IEEE Std 1003.1-2017, Standard for Information Technology -- Portable Operating System Interface (POSIX), The Open Group Base Specifications Issue 7, 2018 Edition, Copyright (C) 2018 by the Institute of Electrical and Electronics Engineers, Inc and The Open Group.

In the event of any discrepancy between this version and the original IEEE and The Open Group Standard, the original IEEE and The Open Group Standard is the referee document. The original Standard can be obtained online at http://www.opengroup.org/unix/online.html .

Any typographical or formatting errors that appear in this page are most likely to have been introduced during the conversion of the source files to man page format. To report such errors, see https://www.kernel.org/doc/man-pages/reporting_bugs.html .

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and that's the whole page babes 🫶 brought to you by IEEE/The Open Group, 2017 — ISASTREAM(3P), signing off. one function, one error code, zero examples, infinite aura. 💅✨👑