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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
       strndup(), 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  only  copies  at  most  n
       characters.  If s is longer than n, only n characters 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 only available when using  the  GNU  GCC  suite,  and
       suffer from the same limitations described in alloca(3).

RETURN VALUE

       The  strdup()  function  returns a pointer to the duplicated string, or
       NULL if insufficient memory was available.

ERRORS

       ENOMEM Insufficient memory available to allocate duplicate string.

CONFORMING TO

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

SEE ALSO

       alloca(3), calloc(3), free(3), malloc(3), realloc(3), wcsdup(3)

COLOPHON

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       description of the project, and information about reporting  bugs,  can
       be found at http://www.kernel.org/doc/man-pages/.