strdupa(3)

1strdup(3)                  Library Functions Manual                  strdup(3)
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NAME

6       strdup, strndup, strdupa, strndupa - duplicate a string
7

LIBRARY

9       Standard C library (libc, -lc)
10

SYNOPSIS

12       #include <string.h>
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14       char *strdup(const char *s);
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16       char *strndup(const char s[.n], size_t n);
17       char *strdupa(const char *s);
18       char *strndupa(const char s[.n], size_t n);
19
20   Feature Test Macro Requirements for glibc (see feature_test_macros(7)):
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22       strdup():
23           _XOPEN_SOURCE >= 500
24               || /* Since glibc 2.12: */ _POSIX_C_SOURCE >= 200809L
25               || /* glibc <= 2.19: */ _BSD_SOURCE || _SVID_SOURCE
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27       strndup():
28           Since glibc 2.10:
29               _POSIX_C_SOURCE >= 200809L
30           Before glibc 2.10:
31               _GNU_SOURCE
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33       strdupa(), strndupa():
34           _GNU_SOURCE
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DESCRIPTION

37       The  strdup() function returns a pointer to a new string which is a du‐
38       plicate of the string s.  Memory for the new string  is  obtained  with
39       malloc(3), and can be freed with free(3).
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41       The strndup() function is similar, but copies at most n bytes.  If s is
42       longer than n, only n bytes are copied, and  a  terminating  null  byte
43       ('\0') is added.
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45       strdupa() and strndupa() are similar, but use alloca(3) to allocate the
46       buffer.
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RETURN VALUE

49       On success, the strdup() function returns a pointer to  the  duplicated
50       string.  It returns NULL if insufficient memory was available, with er‐
51       rno set to indicate the error.
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ERRORS

54       ENOMEM Insufficient memory available to allocate duplicate string.
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ATTRIBUTES

57       For an  explanation  of  the  terms  used  in  this  section,  see  at‐
58       tributes(7).
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60       ┌────────────────────────────────────────────┬───────────────┬─────────┐
61       │Interface                                   │ Attribute     │ Value   │
62       ├────────────────────────────────────────────┼───────────────┼─────────┤
63       │strdup(), strndup(), strdupa(), strndupa()  │ Thread safety │ MT-Safe │
64       └────────────────────────────────────────────┴───────────────┴─────────┘
65

STANDARDS

67       strdup()
68       strndup()
69              POSIX.1-2008.
70
71       strdupa()
72       strndupa()
73              GNU.
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HISTORY

76       strdup()
77              SVr4, 4.3BSD-Reno, POSIX.1-2001.
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79       strndup()
80              POSIX.1-2008.
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82       strdupa()
83       strndupa()
84              GNU.
85