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ulimit(2)                        System Calls                        ulimit(2)



NAME
       ulimit - get and set process limits

SYNOPSIS
       #include <ulimit.h>

       long ulimit(int cmd, /* newlimit */...);

DESCRIPTION
       The  ulimit()  function provides for control over process limits. It is
       effective in limiting the growth of regular files. Pipes are limited to
       PIPE_MAX bytes.

       The cmd values, defined in <&lt;ulimit.h>&gt;, include:

       UL_GETFSIZE     Return  the  soft  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. The
                       return value is the integer part of the soft file  size
                       limit  divided  by 512.  If the result cannot be repre-
                       sented as a long int, the result is unspecified.



       UL_SETFSIZE     Set the hard and soft file size limits for output oper-
                       ations  of the process to the value of the second argu-
                       ment, taken as a long int. Any process may decrease its
                       own  hard  limit,  but  only a process with appropriate
                       privileges may increase the limit. The  new  file  size
                       limit  is  returned. The hard and soft file size limits
                       are set to the specified value multiplied by  512.   If
                       the result would overflow an rlimit_t, the actual value
                       set is unspecified.



       UL_GMEMLIM      Get the maximum possible break value (see brk(2)).



       UL_GDESLIM      Get the current value of the  maximum  number  of  open
                       files per process configured in the system.



RETURN VALUES
       Upon successful completion, ulimit() returns the value of the requested
       limit.  Otherwise, -1 is returned, the limit is not changed, and  errno
       is set to indicate the error.

ERRORS
       The ulimit() function will fail if:

       EINVAL          The cmd argument is not valid.



       EPERM           A  process that has not asserted {PRIV_SYS_RESOURCE} in
                       its effective set is trying to increase its  file  size
                       limit.



USAGE
       Since  all  return values are permissible in a successful situation, an
       application wishing to check for error situations should set  errno  to
       0,  then  call  ulimit(),  and if it returns -1, check if errno is non-
       zero.

       The getrlimit() and setrlimit() functions provide a more general inter-
       face  for  controlling process limits, and are preferred over ulimit().
       See getrlimit(2).

ATTRIBUTES
       See attributes(5) for descriptions of the following attributes:


       tab()    allbox;    cw(2.750000i)|     cw(2.750000i)     lw(2.750000i)|
       lw(2.750000i).   ATTRIBUTE TYPEATTRIBUTE VALUE Interface StabilityStan-
       dard


SEE ALSO
       brk(2), getrlimit(2),  write(2),  attributes(5),  privileges(5),  stan-
       dards(5)



SunOS 5.10                        1 Feb 2003                         ulimit(2)