pathconf(3)

NAME

pathconf, fpathconf − get configurable pathname variables (POSIX)

SYNTAX

#include <unistd.h>

long pathconf(path, name);
char *path;
int name;

long fpathconf(fildes, name);
int fildes, name;

DESCRIPTION

The pathconf() and fpathconf() functions provide a method for the application to determine the current value of a configurable limit or option that is associated with a file or directory.

For pathconf(,), the path argument points to the pathname of a file or directory. For fpathconf(,), the fildes argument is an open file descriptor.

The name argument represents the variable to be queried relative to that file or directory. The following table lists the variables which may be queried and the corresponding value for the name argument. The values for the name argument are defined in the <unistd.h> header file.

Variablename Value

LINK_MAX_PC_LINK_MAX

_PC_MAX_CANON

MAX_INPUT
_PC_MAX_INPUT

NAME_MAX
_PC_NAME_MAX

PATH_MAX
_PC_PATH_MAX

PIPE_BUF
_PC_PIPE_BUF

_POSIX_CHOWN_RESTRICTED
_PC_CHOWN_RESTRICTED

_POSIX_NO_TRUNC
_PC_NO_TRUNC

_POSIX_VDISABLE
_PC_VDISABLE

RETURN VALUE

Upon successful completion, the pathconf() and fpathconf() functions return the current variable value for the file or directory.

If name is an invalid value, pathconf() and fpathconf() return −1 and errno is set to indicate the reason. If the variable corresponding to name is not defined on the system, pathconf() and fpathconf() return −1 without changing the value of errno.

DIAGNOSTICS

The pathconf() and fpathconf() functions fail if the following occurs:

[EINVAL] The value of the name argument is invalid.