NAME
fpathconf, pathconf - get configuration values for files
SYNOPSIS
#include <unistd.h>
long fpathconf(int fd, int name);
long pathconf(char *path, int name);
DESCRIPTION
fpathconf() gets a value for the configuration option name for the open file descriptor fd.
pathconf() gets a value for configuration option name for the filename path.
The corresponding macros defined in <unistd.h> are minimum values; if an application wants to take advantage of values which may change, a call to fpathconf() or pathconf() can be made, which may yield more liberal results.
Setting name equal to one of the following constants returns the following configuration options:
| _PC_LINK_MAX | |
| returns the maximum number of links to the file. If fd or path refer to a directory, then the value applies to the whole directory. The corresponding macro is _POSIX_LINK_MAX. | |
| _PC_MAX_CANON | |
| returns the maximum length of a formatted input line, where fd or path must refer to a terminal. The corresponding macro is _POSIX_MAX_CANON. | |
| _PC_MAX_INPUT | |
| returns the maximum length of an input line, where fd or path must refer to a terminal. The corresponding macro is _POSIX_MAX_INPUT. | |
| _PC_NAME_MAX | |
| returns the maximum length of a filename in the directory path or fd that the process is allowed to create. The corresponding macro is _POSIX_NAME_MAX. | |
| _PC_PATH_MAX | |
| returns the maximum length of a relative pathname when path or fd is the current working directory. The corresponding macro is _POSIX_PATH_MAX. | |
| _PC_PIPE_BUF | |
| returns the size of the pipe buffer, where fd must refer to a pipe or FIFO and path must refer to a FIFO. The corresponding macro is _POSIX_PIPE_BUF. | |
| _PC_CHOWN_RESTRICTED | |
| returns non-zero if the chown(2) call may not be used on this file. If fd or path refer to a directory, then this applies to all files in that directory. The corresponding macro is _POSIX_CHOWN_RESTRICTED. | |
| _PC_NO_TRUNC | |
| returns non-zero if accessing filenames longer than _POSIX_NAME_MAX generates an error. The corresponding macro is _POSIX_NO_TRUNC. | |
| _PC_VDISABLE | |
| returns non-zero if special character processing can be disabled, where fd or path must refer to a terminal. | |
RETURN VALUE
The limit is returned, if one exists. If the system does not have a limit for the requested resource, -1 is returned, and errno is unchanged. If there is an error, -1 is returned, and errno is set to reflect the nature of the error.
CONFORMING TO
POSIX.1-2001.
NOTES
Files with name lengths longer than the value returned for name equal to _PC_NAME_MAX may exist in the given directory.
Some returned values may be huge; they are not suitable for allocating memory.
SEE ALSO
getconf(1), open(2), statfs(2), sysconf(3)
COLOPHON
This page is part of release 3.23 of the Linux man-pages project. A description of the project, and information about reporting bugs, can be found at http://www.kernel.org/doc/man-pages/.
