STRCAT(3P)

💖 STRCAT(3P) — the POSIX Programmer's Manual era 💖

okay bestie, welcome to strcat(3P), straight out of the POSIX Programmer's Manual. this is the version where we read the actual standard, not the Linux-flavoured remix.

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🫶 PROLOG

This manual page is part of the POSIX Programmer's Manual. The Linux implementation of this interface may differ (consult the corresponding Linux manual page for details of Linux behavior), or the interface may not be implemented on Linux. no cap, always double-check which one you're reading 💅

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✨ NAME ✨

strcat — concatenate two strings. that's it. that's the whole job. iconic.

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🌸 SYNOPSIS 🌸

#include <string.h>

char *strcat(char *restrict s1, const char *restrict s2);

look at those restricts. she's particular. 👑

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🦋 DESCRIPTION 🦋

The functionality described on this reference page is aligned with the ISO C standard. Any conflict between the requirements described here and the ISO C standard is unintentional. This volume of POSIX.1‐2017 defers to the ISO C standard. so if the two ever beef, ISO C wins, periodt.

The strcat() function shall append a copy of the string pointed to by s2 (including the terminating NUL character) to the end of the string pointed to by s1. The initial byte of s2 overwrites the NUL character at the end of s1.

🚨 and here's the part where you sit up straight: if copying takes place between objects that overlap, the behavior is undefined. not "a little weird". not "probably fine". undefined. don't do it. 💀

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💅 RETURN VALUE 💅

The strcat() function shall return s1. that's your girl, back again, now with more string.

no return value is reserved to indicate an error. so like… she literally cannot tell you something went wrong. there's no sad face return code. she just vibes and returns s1. 😭

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🎀 ERRORS 🎀

No errors are defined.

The following sections are informative.

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🌈 EXAMPLES 🌈

None. we love a low-effort section tbh.

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🍓 APPLICATION USAGE 🍓

This version is aligned with the ISO C standard; this does not affect compatibility with XPG3 applications. Reliable error detection by this function was never guaranteed. fr fr, never was. don't come for her about it.

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⭐ RATIONALE ⭐

None.

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🔥 FUTURE DIRECTIONS 🔥

None.

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👑 SEE ALSO 👑

• strncat()
• The Base Definitions volume of POSIX.1‐2017, <string.h>

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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, bestie 💖 brought to you by IEEE/The Open Group, 2017 — STRCAT(3P), forever and always. mwah. 🫶