confstr

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



NAME
       confstr - get configuration dependent string variables

SYNOPSIS
       #define _POSIX_C_SOURCE 2
       or
       #define _XOPEN_SOURCE
       #include <unistd.h>

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

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_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 characters if necessary, with a
       null character as termination.  This can be detected by  comparing  the
       return value of confstr() against len.

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

RETURN VALUE
       If name does not correspond to a valid  configuration  variable,  conf-
       str() returns 0.

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

ERRORS
       If the value of name is invalid, errno is set to EINVAL.

CONFORMING TO
       proposed POSIX.2

BUGS
       POSIX.2 is not yet an approved standard; the information in  this  man-
       page is subject to change.

SEE ALSO
       sh(1), exec(3), system(3)



GNU                               1993-04-17                        CONFSTR(3)