PATHCONF(2)						      BSD System Calls Manual						       PATHCONF(2)

NAME

     pathconf, fpathconf -- get configurable pathname variables

SYNOPSIS

     #include <unistd.h>

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

     long
     fpathconf(int fd, int name);

DESCRIPTION

     The pathconf() and fpathconf() functions provides a method for applications to determine the current value of a configurable system limit or
     option variable associated with a pathname or file descriptor.

     For pathconf, the path argument is the name of a file or directory.  For fpathconf, the fd argument is an open file descriptor.  The name
     argument specifies the system variable to be queried.  Symbolic constants for each name value are found in the include file <unistd.h>.

     The available values are as follows:

     _PC_LINK_MAX
	     The maximum file link count.

     _PC_MAX_CANON
	     The maximum number of bytes in terminal canonical input line.

     _PC_MAX_INPUT
	     The minimum maximum number of bytes for which space is available in a terminal input queue.

     _PC_NAME_MAX
	     The maximum number of bytes in a file name.

     _PC_PATH_MAX
	     The maximum number of bytes in a pathname.

     _PC_PIPE_BUF
	     The maximum number of bytes which will be written atomically to a pipe.

     _PC_CHOWN_RESTRICTED
	     Return 1 if appropriate privileges are required for the chown(2) system call, otherwise 0.

     _PC_NO_TRUNC
	     Return 1 if file names longer than KERN_NAME_MAX are truncated.

     _PC_VDISABLE
	     Returns the terminal character disabling value.

RETURN VALUES

     If the call to pathconf or fpathconf is not successful, -1 is returned and errno is set appropriately.  Otherwise, if the variable is associ-
     ated with functionality that does not have a limit in the system, -1 is returned and errno is not modified.  Otherwise, the current variable
     value is returned.

ERRORS

     If any of the following conditions occur, the pathconf and fpathconf functions shall return -1 and set errno to the corresponding value.

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

     [EINVAL]		The implementation does not support an association of the variable name with the associated file.
     Pathconf() will fail if:

     [ENOTDIR]	     A component of the path prefix is not a directory.

     [ENAMETOOLONG]  A component of a pathname exceeded 255 characters, or an entire path name exceeded 1023 characters.

     [ENOENT]	     The named file does not exist.

     [EACCES]	     Search permission is denied for a component of the path prefix.

     [ELOOP]	     Too many symbolic links were encountered in translating the pathname.

     [EIO]	     An I/O error occurred while reading from or writing to the file system.

     Fpathconf() will fail if:

     [EBADF]   fd is not a valid open file descriptor.

     [EIO]     An I/O error occurred while reading from or writing to the file system.

SEE ALSO

     sysctl(3)

HISTORY

     The pathconf and fpathconf functions first appeared in 4.4BSD.

4th Berkeley Distribution					   June 4, 1993 					 4th Berkeley Distribution