1 .\" (c) 1993 by Thomas Koenig (ig25@rz.uni-karlsruhe.de)
3 .\" Permission is granted to make and distribute verbatim copies of this
4 .\" manual provided the copyright notice and this permission notice are
5 .\" preserved on all copies.
7 .\" Permission is granted to copy and distribute modified versions of this
8 .\" manual under the conditions for verbatim copying, provided that the
9 .\" entire resulting derived work is distributed under the terms of a
10 .\" permission notice identical to this one.
12 .\" Since the Linux kernel and libraries are constantly changing, this
13 .\" manual page may be incorrect or out-of-date. The author(s) assume no
14 .\" responsibility for errors or omissions, or for damages resulting from
15 .\" the use of the information contained herein. The author(s) may not
16 .\" have taken the same level of care in the production of this manual,
17 .\" which is licensed free of charge, as they might when working
20 .\" Formatted or processed versions of this manual, if unaccompanied by
21 .\" the source, must acknowledge the copyright and authors of this work.
23 .\" Modified Sat Jul 24 19:53:02 1993 by Rik Faith (faith@cs.unc.edu)
24 .\" FIXME Many more values for 'name' are supported, some of which
25 .\" are documented under 'info confstr'.
26 .\" See <bits/confname.h> for the rest.
27 .\" These should all be added to this page.
28 .\" See also the SUSv3 specification of confstr()
29 .TH CONFSTR 3 1993-04-17 "GNU" "Linux Programmer's Manual"
31 confstr \- get configuration dependent string variables
34 .B #define _POSIX_C_SOURCE 2
36 .B #define _XOPEN_SOURCE
38 .B #include <unistd.h>
40 .BI "size_t confstr(int " "name" ", char *" buf ", size_t " len );
44 gets the value of configuration-dependent string variables.
48 argument is the system variable to be queried.
49 The following variables are supported:
51 .BR _CS_GNU_LIBC_VERSION " (GNU C library only; since glibc 2.3.2)"
52 A string which identifies the GNU C library version on this system
55 .BR _CS_GNU_LIBPTHREAD_VERSION " (GNU C library only; since glibc 2.3.2)"
56 A string which identifies the POSIX implementation supplied by this
57 C library (e.g, "NPTL 2.3.4" or "linuxthreads-0.10").
62 variable which indicates where all the POSIX.2 standard utilities can
71 copies the value of the string to
75 characters if necessary, with a null byte ('\\0') as terminator.
76 This can be detected by comparing the return value of
87 just returns the value as defined below.
91 does not correspond to a valid configuration variable,
95 The following code fragment determines the path where to find
96 the POSIX.2 system utilities:
101 char *pathbuf; size_t n;
103 n = confstr(_CS_PATH,NULL,(size_t)0);
104 if ((pathbuf = malloc(n)) == NULL) abort();
105 confstr(_CS_PATH, pathbuf, n);
116 POSIX.2 is not yet an approved standard; the information in this
117 manpage is subject to change.