confstr(3) 맨 페이지 - 윈디하나의 솔라나라

개요

섹션
맨 페이지 이름
검색(S)

confstr(3)

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

NAME
       confstr - get configuration dependent string variables

SYNOPSIS
       #include <unistd.h>

       size_t confstr(int name, char *buf, size_t len);

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

       confstr(): _POSIX_C_SOURCE >= 2 || _XOPEN_SOURCE

DESCRIPTION
       confstr() gets the value of configuration-dependent string variables.

       The  name argument is the system variable to be queried.  The following
       variables are supported:

       _CS_GNU_LIBC_VERSION (GNU C library only; since glibc 2.3.2)
              A string which identifies the GNU C library version on this sys‐
              tem (e.g., "glibc 2.3.4").

       _CS_GNU_LIBPTHREAD_VERSION (GNU C library only; since glibc 2.3.2)
              A string which identifies the POSIX implementation  supplied  by
              this C library (e.g., "NPTL 2.3.4" or "linuxthreads-0.10").

       _CS_PATH
              A  value  for  the  PATH  variable which indicates where all the
              POSIX.2 standard utilities can be found.

       If buf is not NULL and len is not zero, confstr() copies the  value  of
       the  string to buf truncated to len - 1 bytes if necessary, with a null
       byte ('\0') as terminator.  This can be detected by comparing  the  re‐
       turn value of confstr() against len.

       If len is zero and buf is NULL, confstr() just returns the value as de‐
       fined below.

RETURN VALUE
       If name is a valid configuration variable, confstr() returns the number
       of  bytes  (including the terminating null byte) that would be required
       to hold the entire value of that variable.  This value may  be  greater
       than len, which means that the value in buf is truncated.

       If  name  is a valid configuration variable, but that variable does not
       have a value, then confstr() returns 0.  If name does not correspond to
       a valid configuration variable, confstr() returns 0, and errno  is  set
       to EINVAL.

ERRORS
       EINVAL The value of name is invalid.

ATTRIBUTES
       For  an  explanation  of  the  terms  used in this section, see attrib‐
       utes(7).  allbox; lb lb lb l l l.  Interface Attribute Value  T{  conf‐
       str() T}   Thread safety  MT-Safe

CONFORMING TO
       POSIX.1-2001, POSIX.1-2008.

EXAMPLE
       The  following  code  fragment  determines  the  path where to find the
       POSIX.2 system utilities:

           char *pathbuf;
           size_t n;

           n = confstr(_CS_PATH, NULL, (size_t) 0);
           pathbuf = malloc(n);
           if (pathbuf == NULL)
               abort();
           confstr(_CS_PATH, pathbuf, n);

SEE ALSO
       getconf(1), sh(1), exec(3), fpathconf(3), pathconf(3), sysconf(3), sys‐
       tem(3)

COLOPHON
       This page is part of release 5.02 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
       https://www.kernel.org/doc/man-pages/.

GNU                               2019-03-06                        CONFSTR(3)
맨 페이지 내용의 저작권은 맨 페이지 작성자에게 있습니다.
RSS ATOM XHTML 5 CSS3