1 .\" Copyright 1993 David Metcalfe (david@prism.demon.co.uk)
3 .\" %%%LICENSE_START(VERBATIM)
4 .\" Permission is granted to make and distribute verbatim copies of this
5 .\" manual provided the copyright notice and this permission notice are
6 .\" preserved on all copies.
8 .\" Permission is granted to copy and distribute modified versions of this
9 .\" manual under the conditions for verbatim copying, provided that the
10 .\" entire resulting derived work is distributed under the terms of a
11 .\" permission notice identical to this one.
13 .\" Since the Linux kernel and libraries are constantly changing, this
14 .\" manual page may be incorrect or out-of-date. The author(s) assume no
15 .\" responsibility for errors or omissions, or for damages resulting from
16 .\" the use of the information contained herein. The author(s) may not
17 .\" have taken the same level of care in the production of this manual,
18 .\" which is licensed free of charge, as they might when working
21 .\" Formatted or processed versions of this manual, if unaccompanied by
22 .\" the source, must acknowledge the copyright and authors of this work.
25 .\" References consulted:
26 .\" Linux libc source code
27 .\" Lewine's _POSIX Programmer's Guide_ (O'Reilly & Associates, 1991)
29 .\" Modified Sun Jul 25 10:41:34 1993 by Rik Faith (faith@cs.unc.edu)
30 .\" Modified Wed Oct 17 01:12:26 2001 by John Levon <moz@compsoc.man.ac.uk>
31 .TH STRDUP 3 2012-05-10 "GNU" "Linux Programmer's Manual"
33 strdup, strndup, strdupa, strndupa \- duplicate a string
36 .B #include <string.h>
38 .BI "char *strdup(const char *" s );
40 .BI "char *strndup(const char *" s ", size_t " n );
42 .BI "char *strdupa(const char *" s );
44 .BI "char *strndupa(const char *" s ", size_t " n );
48 Feature Test Macro Requirements for glibc (see
49 .BR feature_test_macros (7)):
56 _SVID_SOURCE || _BSD_SOURCE || _XOPEN_SOURCE\ >=\ 500 ||
57 _XOPEN_SOURCE\ &&\ _XOPEN_SOURCE_EXTENDED
59 || /* Since glibc 2.12: */ _POSIX_C_SOURCE\ >=\ 200809L
66 POSIX_C_SOURCE\ >=\ 200809L || _XOPEN_SOURCE\ >=\ 700
80 function returns a pointer to a new string which
81 is a duplicate of the string \fIs\fP.
82 Memory for the new string is
90 function is similar, but only copies at most
92 If \fIs\fP is longer than \fIn\fP, only \fIn\fP
93 bytes are copied, and a terminating null byte (\(aq\\0\(aq) is added.
100 to allocate the buffer.
101 They are only available when using the GNU
102 GCC suite, and suffer from the same limitations described in
107 function returns a pointer to the duplicated
108 string, or NULL if insufficient memory was available.
112 Insufficient memory available to allocate duplicate string.
114 .\" 4.3BSD-Reno, not (first) 4.3BSD.
116 conforms to SVr4, 4.3BSD, POSIX.1-2001.
118 conforms to POSIX.1-2008.