|FPATHCONF(3)||Linux Programmer's Manual||FPATHCONF(3)|
NAME¶fpathconf, pathconf - get configuration values for files
#include <unistd.h> long fpathconf(int fd, int name);
long pathconf(const 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:
- 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.
- 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.
- returns the maximum length of an input line, where fd or path must refer to a terminal. The corresponding macro is _POSIX_MAX_INPUT.
- 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.
- returns the maximum length of a relative pathname when path or fd is the current working directory. The corresponding macro is _POSIX_PATH_MAX.
- 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.
- returns 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.
- returns nonzero if accessing filenames longer than _POSIX_NAME_MAX generates an error. The corresponding macro is _POSIX_NO_TRUNC.
- returns nonzero 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.
ATTRIBUTES¶For an explanation of the terms used in this section, see attributes(7).
|fpathconf (), pathconf ()||Thread safety||MT-Safe|
CONFORMING TO¶POSIX.1-2001, POSIX.1-2008.
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), confstr(3), sysconf(3)
COLOPHON¶This page is part of release 4.10 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/.