strndupa

STRDUP(3)                  Linux Programmer's Manual                 STRDUP(3)

NAME
       strdup, strndup, strdupa, strndupa - duplicate a string

SYNOPSIS
       #include <string.h>

       char *strdup(const char *s);

       char *strndup(const char *s, size_t n);
       char *strdupa(const char *s);
       char *strndupa(const char *s, size_t n);

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

       strdup():
           _SVID_SOURCE || _BSD_SOURCE || _XOPEN_SOURCE >= 500 ||
           _XOPEN_SOURCE && _XOPEN_SOURCE_EXTENDED
           || /* Since glibc 2.12: */ _POSIX_C_SOURCE >= 200809L
       strndup():
           Since glibc 2.10:
               _POSIX_C_SOURCE >= 200809L || _XOPEN_SOURCE >= 700
           Before glibc 2.10:
               _GNU_SOURCE
       strdupa(), strndupa(): _GNU_SOURCE

DESCRIPTION
       The strdup() function returns a pointer to a  new  string  which  is  a
       duplicate  of the string s.  Memory for the new string is obtained with
       malloc(3), and can be freed with free(3).

       The strndup() function is similar, but copies at most n bytes.  If s is
       longer  than  n,  only  n bytes are copied, and a terminating null byte
       ('\0') is added.

       strdupa() and strndupa() are similar, but use alloca(3) to allocate the
       buffer.  They are available only when using the GNU GCC suite, and suf-
       fer from the same limitations described in alloca(3).

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

ERRORS
       ENOMEM Insufficient memory available to allocate duplicate string.

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

       +--------------------------------+---------------+---------+
       |Interface                       | Attribute     | Value   |
       +--------------------------------+---------------+---------+
       |strdup(), strndup(), strdupa(), | Thread safety | MT-Safe |
       |strndupa()                      |               |         |
       +--------------------------------+---------------+---------+

CONFORMING TO
       strdup() conforms to SVr4, 4.3BSD, POSIX.1-2001.  strndup() conforms to
       POSIX.1-2008.  strdupa() and strndupa() are GNU extensions.

SEE ALSO
       alloca(3), calloc(3), free(3), malloc(3), realloc(3),  string(3),  wcs-
       dup(3)

COLOPHON
       This  page  is  part of release 4.04 of the Linux man-pages project.  A
       description of the project, information about reporting bugs,  and  the
       latest     version     of     this    page,    can    be    found    at
       http://www.kernel.org/doc/man-pages/.

GNU                               2015-03-29                         STRDUP(3)
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