return the value of a configurable limit associated with a
file
#include <unistd.h>
long fpathconf( int filedes, int name );
The fpathconf() function returns a value of a configurable limit
indicated by name that is associated with the file
indicated by filedes.
Configurable limits are defined in <unistd.h>, and contain
at least the following values:
- _PC_LINK_MAX
- Maximum value of a file's link count.
- _PC_MAX_CANON
- Maximum number of bytes in a terminal's canonical input buffer
(edit buffer).
- _PC_MAX_INPUT
- Maximum number of bytes in a terminal's raw input buffer.
- _PC_NAME_MAX
- Maximum number of bytes in a file name (not including the terminating
null).
- _PC_PATH_MAX
- Maximum number of bytes in a pathname (not including the terminating
null).
- _PC_PIPE_BUF
- Maximum number of bytes that can be written atomically when writing to
a pipe.
- _PC_CHOWN_RESTRICTED
- If defined (not -1), indicates that the use of the chown()
function is restricted to a process with appropriate privileges, and to
changing the group ID of a file to the effective group ID of the
process or to one of its supplementary group IDs.
- _PC_NO_TRUNC
- If defined (not -1), indicates that the use of pathname components
longer than the value given by _PC_NAME_MAX
generates an error.
- _PC_VDISABLE
- If defined (not -1), this is the character value that can be used to
individually disable special control characters in the
termios control structure.
The requested configurable limit.
If an error occurs, -1 is returned and errno is set.
- EINVAL
- name is invalid, or the indicated limit is not
supported for this filedes.
- EBADF
- The argument filedes is invalid.
#include <stdio.h>
#include <unistd.h>
void main()
{
long value;
value = fpathconf( 0, _PC_MAX_INPUT );
printf( "Input buffer size is %ld bytes\n", value );
}
POSIX 1003.1
Safety: | |
Interrupt handler |
No |
Signal handler |
Yes, but modifies errno |
Thread |
Yes |
errno,
pathconf()