strchrnul(3) — Linux manual page

strchrnul(3)             Library Functions Manual            strchrnul(3)

NAME         top

       strchrnul - string search character or NUL

LIBRARY         top

       Standard C library (libc, -lc)

SYNOPSIS         top

       #define _GNU_SOURCE  /* See feature_test_macros(7) */
       #include <string.h>

       char *strchrnul(const char *s, int c);

DESCRIPTION         top

       The strchrnul() function is like strchr(3) except that if c is not
       found in s, then it returns a pointer to the null byte at the end
       of s.

       It is equivalent to both of the following expressions:

           strchr(s, c) ?: strnul(s)
           s + strcspn(s, (char [2]){c, '\0'})

RETURN VALUE         top

       The strchrnul() function returns a pointer to the matched
       character, or a pointer to the null byte at the end of s if the
       character is not found.

ATTRIBUTES         top

       For an explanation of the terms used in this section, see
       attributes(7).
       ┌──────────────────────────────────────┬───────────────┬─────────┐
       │ Interface                            │ Attribute     │ Value   │
       ├──────────────────────────────────────┼───────────────┼─────────┤
       │ strchrnul()                          │ Thread safety │ MT-Safe │
       └──────────────────────────────────────┴───────────────┴─────────┘

STANDARDS         top

       GNU.

HISTORY         top

       glibc 2.1.1, FreeBSD 10, NetBSD 8.

SEE ALSO         top

       string(3), strchr(3), strnul(3), strcspn(3), strspn(3)

COLOPHON         top

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Linux man-pages 6.18            2026-02-25                   strchrnul(3)

Pages that refer to this page: strchr(3)

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