vlimit - control maximum system resource consumption
This facility is superseded by getrlimit(2).
Limits the consumption by the current process and each process it cre-
ates to not individually exceed value on the specified resource. If
value is specified as -1, then the current limit is returned and the
limit is unchanged. The resources which are currently controllable
LIM_NORAISE A pseudo-limit; if set non-zero then the limits may not
be raised. Only the super-user may remove the noraise
LIM_CPU the maximum number of cpu-seconds to be used by each
LIM_FSIZE the largest single file which can be created
LIM_DATA the maximum growth of the data+stack region via sbrk(2)
beyond the end of the program text
LIM_STACK the maximum size of the automatically-extended stack
LIM_CORE the size of the largest core dump that will be created.
LIM_MAXRSS a soft limit for the amount of physical memory (in
bytes) to be given to the program. If memory is tight,
the system will prefer to take memory from processes
which are exceeding their declared LIM_MAXRSS.
Because this information is stored in the per-process information this
system call must be executed directly by the shell if it is to affect
all future processes created by the shell; limit is thus a built-in
command to csh(1).
The system refuses to extend the data or stack space when the limits
would be exceeded in the normal way; a break call fails if the data
space limit is reached, or the process is killed when the stack limit
is reached (since the stack cannot be extended, there is no way to send
A file i/o operation which would create a file which is too large will
cause a signal SIGXFSZ to be generated, this normally terminates the
process, but may be caught. When the cpu time limit is exceeded, a
signal SIGXCPU is sent to the offending process; to allow it time to
process the signal it is given 5 seconds grace by raising the cpu time
If LIM_NORAISE is set, then no grace should be given when the cpu time
limit is exceeded.
There should be limit and unlimit commands in sh(1) as well as in csh.
This call is peculiar to this version of UNIX. The options and speci-
fications of this system call and even the call itself are subject to
change. It may be extended or replaced by other facilities in future
versions of the system.
4th Berkeley Distribution 18 July 1983 VLIMIT(3C)