strlen(3) - Linux manual page (original) (raw)

strlen(3) Library Functions Manual strlen(3)

NAME top

   strlen - calculate the length of a string

LIBRARY top

   Standard C library (_libc_, _-lc_)

SYNOPSIS top

   **#include <string.h>**

   **size_t strlen(const char ***_s_**);**

DESCRIPTION top

   The **strlen**() function calculates the length of the string pointed
   to by _s_, excluding the terminating null byte ('\0').

RETURN VALUE top

   The **strlen**() function returns the number of bytes in the string
   pointed to by _s_.

ATTRIBUTES top

   For an explanation of the terms used in this section, see
   [attributes(7)](../man7/attributes.7.html).
   ┌──────────────────────────────────────┬───────────────┬─────────┐
   │ **Interface** │ **Attribute** │ **Value** │
   ├──────────────────────────────────────┼───────────────┼─────────┤
   │ **strlen**()                             │ Thread safety │ MT-Safe │
   └──────────────────────────────────────┴───────────────┴─────────┘

STANDARDS top

   C11, POSIX.1-2008.

HISTORY top

   POSIX.1-2001, C89, SVr4, 4.3BSD.

NOTES top

   In cases where the input buffer may not contain a terminating null
   byte, [strnlen(3)](../man3/strnlen.3.html) should be used instead.

SEE ALSO top

   [string(3)](../man3/string.3.html), [strnlen(3)](../man3/strnlen.3.html), [wcslen(3)](../man3/wcslen.3.html), [wcsnlen(3)](../man3/wcsnlen.3.html)

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Linux man-pages 6.10 2024-07-23 strlen(3)

Pages that refer to this page:lber-types(3), memchr(3), pmfstring(3), regex(3), strchr(3), string(3), strnlen(3), wcslen(3), signal-safety(7)