strndup(3)                 Library Functions Manual                 strndup(3)

NAME
       strndup - nonstring duplicate-into-string

LIBRARY
       Standard C library (libc, -lc)

SYNOPSIS
       #include <string.h>  // see memory.h(3head)

       char *strndup(size_t n;
                     const char strn[n], size_t n);

   Feature Test Macro Requirements for glibc (see feature_test_macros(7)):

       strndup():
           Since glibc 2.10:
               _POSIX_C_SOURCE >= 200809L
           Before glibc 2.10:
               _GNU_SOURCE

DESCRIPTION
       This function duplicates at most n nonnull characters from the array
       pointed to by strn, followed by a null character, into new memory
       obtained with malloc(3).

RETURN VALUE
       On success, the strndup() function returns a pointer to the duplicated
       string.  It returns NULL if insufficient memory was available, with
       errno set to indicate the error.

ERRORS
       See malloc(3).

ATTRIBUTES
       For an explanation of the terms used in this section, see
       attributes(7).

       +--------------------------------------------+---------------+---------+
       |Interface                                   | Attribute     | Value   |
       +--------------------------------------------+---------------+---------+
       |strndup ()                                  | Thread safety | MT-Safe |
       +--------------------------------------------+---------------+---------+
STANDARDS
       POSIX.1-2008.

HISTORY
       POSIX.1-2008.

SEE ALSO
       memory.h(3head), malloc(3), strndupa(3)

Linux man-pages 6.19              2026-08-17                        strndup(3)