fpathconf, pathconf — get configuration values for files
#include <unistd.h>
long
fpathconf( |
int fd, |
int name); |
long
pathconf( |
const char *path, |
int name); |
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_MAXreturns 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_CANONreturns 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_INPUTreturns 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_MAXreturns 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_MAXreturns 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_BUFreturns 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_RESTRICTEDreturns nonzero 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_TRUNCreturns nonzero if accessing filenames longer than
_POSIX_NAME_MAX generates
an error. The corresponding macro is _POSIX_NO_TRUNC.
_PC_VDISABLEreturns nonzero if special character processing can
be disabled, where fd or path must refer to a
terminal.
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.
For an explanation of the terms used in this section, see attributes(7).
| Interface | Attribute | Value |
fpathconf(), pathconf() |
Thread safety | MT-Safe |
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.
This page is part of release 4.07 of the Linux man-pages project. A
description of the project, information about reporting bugs,
and the latest version of this page, can be found at
https://www.kernel.org/doc/man−pages/.
|
Copyright (c) 1993 by Thomas Koenig (ig25rz.uni-karlsruhe.de) %%%LICENSE_START(VERBATIM) Permission is granted to make and distribute verbatim copies of this manual provided the copyright notice and this permission notice are preserved on all copies. Permission is granted to copy and distribute modified versions of this manual under the conditions for verbatim copying, provided that the entire resulting derived work is distributed under the terms of a permission notice identical to this one. Since the Linux kernel and libraries are constantly changing, this manual page may be incorrect or out-of-date. The author(s) assume no responsibility for errors or omissions, or for damages resulting from the use of the information contained herein. The author(s) may not have taken the same level of care in the production of this manual, which is licensed free of charge, as they might when working professionally. Formatted or processed versions of this manual, if unaccompanied by the source, must acknowledge the copyright and authors of this work. %%%LICENSE_END Modified Wed Jul 28 11:12:26 1993 by Rik Faith (faithcs.unc.edu) FIXME Probably all of the following should be documented: _PC_SYNC_IO, _PC_ASYNC_IO, _PC_PRIO_IO, _PC_SOCK_MAXBUF, _PC_FILESIZEBITS, _PC_REC_INCR_XFER_SIZE, _PC_REC_MAX_XFER_SIZE, _PC_REC_MIN_XFER_SIZE, _PC_REC_XFER_ALIGN, _PC_ALLOC_SIZE_MIN, _PC_SYMLINK_MAX, _PC_2_SYMLINKS |