confstr - get configuration dependent string variables
#define _POSIX_C_SOURCE 2
size_t confstr(int name, char *buf, size_t len);
confstr() gets the value of configuration - dependent string variables.
The name argument is the system variable to be queried. The following
variables are supported:
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
If name does not correspond to a valid configuration variable, conf-
str() returns 0.
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);
If the value of name is invalid, errno is set to EINVAL.
POSIX.2 is not yet an approved standard; the information in this manpage
is subject to change.
sh(1), exec(3), system(3)
GNU 1993-04-17 CONFSTR(3)
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