confstr
- get string-valued configurable variables
LIBRARY
Lb libc
SYNOPSIS
#include <unistd.h> size_t
confstr (int name char *buf size_t len);
DESCRIPTION
This interface is specified by
St -p1003.1-2001 .
A more flexible (but non-portable) interface is provided by
sysctl(3).
The
confstr ();
function provides a method for applications to get configuration
defined string values.
Shell programmers needing access to these parameters should use the
getconf(1)
utility.
The
Fa name
argument specifies the system variable to be queried.
Symbolic constants for each name value are found in the include file
In unistd.h .
The
Fa len
argument specifies the size of the buffer referenced by the
argument
Fa buf .
If
Fa len
is non-zero,
Fa buf
is a non-null pointer, and
Fa name
has a value, up to
Fa len
- 1 bytes of the value are copied into the buffer
Fa buf .
The copied value is always null terminated.
The available values are as follows:
_CS_PATH
Return a value for the
PATH
environment variable that finds all the standard utilities.
RETURN VALUES
If the call to
confstr ();
is not successful, 0 is returned and
errno
is set appropriately.
Otherwise, if the variable does not have a configuration defined value,
0 is returned and
errno
is not modified.
Otherwise, the buffer size needed to hold the entire configuration-defined
value is returned.
If this size is greater than the argument
Fa len ,
the string in
Fa buf
was truncated.
ERRORS
The
confstr ();
function may fail and set
errno
for any of the errors specified for the library functions
malloc(3)
and
sysctl(3).
In addition, the following errors may be reported:
