ULIMIT(S) UNIX System V ULIMIT(S)
Name
ulimit - get and set user limits
Syntax
long ulimit (cmd, newlimit)
int cmd;
long newlimit;
Description
This function provides for control over process limits. The
cmd values available are:
1 Get the regular file size limit of the process. The
limit is in units of 512-byte blocks and is inherited
by child processes. Files of any size can be read.
2 Set the regular file size limit of the process to the
value of newlimit. Any process may decrease this
limit, but only a process with an effective user ID of
super-user may increase the limit. ulimit fails and
the limit is unchanged if a process with an effective
user ID other than super-user attempts to increase its
regular file size limit. [EPERM]
3 Get the maximum possible break value (see brk(S)).
4 Return configured value of NOFiles, the value for the
maximum number of open files per process.
See Also
brk(S), write(S)
Diagnostics
Upon successful completion, a non-negative value is
returned. Otherwise, a value of -1 is returned and errno is
set to indicate the error.
Warning
ulimit is effective in limiting the growth of regular files.
Pipes are currently limited to 5,120 bytes.
Standards Conformance
ulimit is conformant with:
AT&T SVID Issue 2, Select Code 307-127;
and The X/Open Portability Guide II of January 1987.
(printed 6/20/89)