ulimit - get and set user limits


   #include <ulimit.h>

   long ulimit(int cmd, long newlimit);


   Warning: this routine is obsolete.  Use getrlimit(2), setrlimit(2), and
   sysconf(3) instead.  For the shell command ulimit(), see bash(1).

   The ulimit() call will get or set some limit for the  calling  process.
   The cmd argument can have one of the following values.

          Return the limit on the size of a file, in units of 512 bytes.

          Set the limit on the size of a file.

   3      (Not  implemented  for  Linux.)   Return  the  maximum  possible
          address of the data segment.

   4      (Implemented but no symbolic  constant  provided.)   Return  the
          maximum number of files that the calling process can open.


   On  success,  ulimit()  returns  a  nonnegative value.  On error, -1 is
   returned, and errno is set appropriately.


   EPERM  A unprivileged process tried to increase a limit.


   For  an  explanation  of  the  terms  used   in   this   section,   see

   Interface  Attribute      Value   
   ulimit()   Thread safety  MT-Safe 


   SVr4, POSIX.1-2001.  POSIX.1-2008 marks ulimit() as obsolete.


   bash(1), getrlimit(2), setrlimit(2), sysconf(3)


   This  page  is  part of release 4.09 of the Linux man-pages project.  A
   description of the project, information about reporting bugs,  and  the
   latest     version     of     this    page,    can    be    found    at


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