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                                                               vlimit(3c)



        _________________________________________________________________
        vlimit
        control maximum system resource consumption
        _________________________________________________________________


        SYNTAX

        #include <sys/vlimit.h>

        vlimit(resource, value)


        DESCRIPTION

        Limits the consumption by the current process and each process it
        creates 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 are:

        LIMNORAISE    A pseudo-limit; if set non-zero then the limits
                       may not be raised.  Only the super-user may remove
                       the noraise restriction.

        LIMCPU        Maximum number of cpu-seconds to be used by each
                       process

        LIMFSIZE      Size of the largest single file that can be
                       created

        LIMDATA       Maximum growth beyond the end of program text of
                       the data+stack region via sbrk(2)

        LIMSTACK      Maximum size of the automatically-extended stack
                       region

        LIMCORE       Size of the largest core dump that may be created.

        LIMMAXRSS     Soft limit for the amount of physical memory (in
                       bytes) to be given to the program.  This
                       information is specified for the system's benefit;
                       if memory is tight, the system will prefer to take
                       memory from processes that are exceeding their
                       declared LIM_MAXRSS.

        Because specifications from this call are 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).




        DG/UX 4.00                                                 Page 1
               Licensed material--property of copyright holder(s)





                                                               vlimit(3c)



        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 signal).

        A file I/O operation that would violate file-size limits during
        creation will cause a signal SIGXFSZ to be generated. This signal
        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 the process time to handle the signal, it adds
        five seconds to the CPU time limit.


        FILES

             /usr/lib/libproto/lib3c.a


        SEE ALSO

        csh(1)


        BUGS

        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.























        DG/UX 4.00                                                 Page 2
               Licensed material--property of copyright holder(s)



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