strnul(3) — Linux manual page

strnul(3)                Library Functions Manual               strnul(3)

NAME         top

       strnul - string search NUL

LIBRARY         top

       gnulib - The GNU Portability Library

SYNOPSIS         top

       #include <string.h>

       char *strnul(char *s);
       const char *strnul(const char *s);

DESCRIPTION         top

       strnul() calculates the position of the terminating null byte
       ('\0') in the string pointed to by s.

       It is equivalent to both of the following expressions:

           s + strlen(s)
           strchr(s, '\0')

RETURN VALUE         top

       strnul() returns a pointer to the terminating null byte in the
       string pointed to by s.

ATTRIBUTES         top

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

STANDARDS         top

       GNU.

HISTORY         top

       gnulib 202607.

SEE ALSO         top

       strlen(3), strchr(3), string(3)

COLOPHON         top

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

Pages that refer to this page: rawmemchr(3),  strchr(3),  strchrnul(3),  strlen(3)

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