<sys/resource.h>(0P)                                POSIX Programmer's Manual                               <sys/resource.h>(0P)



NAME
       sys/resource.h - definitions for XSI resource operations

SYNOPSIS
       #include <sys/resource.h>

DESCRIPTION
       The  <sys/resource.h>  header  shall  define the following symbolic constants as possible values of the which argument of
       getpriority() and setpriority():

       PRIO_PROCESS
              Identifies the who argument as a process ID.

       PRIO_PGRP
              Identifies the who argument as a process group ID.

       PRIO_USER
              Identifies the who argument as a user ID.


       The following type shall be defined through typedef:

       rlim_t Unsigned integer type used for limit values.


       The following symbolic constants shall be defined:

       RLIM_INFINITY
              A value of rlim_t indicating no limit.

       RLIM_SAVED_MAX
              A value of type rlim_t indicating an unrepresentable saved hard limit.

       RLIM_SAVED_CUR
              A value of type rlim_t indicating an unrepresentable saved soft limit.


       On implementations where all resource  limits  are  representable  in  an  object  of  type  rlim_t,  RLIM_SAVED_MAX  and
       RLIM_SAVED_CUR need not be distinct from RLIM_INFINITY.

       The following symbolic constants shall be defined as possible values of the who parameter of getrusage():

       RUSAGE_SELF
              Returns information about the current process.

       RUSAGE_CHILDREN
              Returns information about children of the current process.


       The <sys/resource.h> header shall define the rlimit structure that includes at least the following members:


              rlim_t rlim_cur  The current (soft) limit.
              rlim_t rlim_max  The hard limit.

       The <sys/resource.h> header shall define the rusage structure that includes at least the following members:


              struct timeval ru_utime  User time used.
              struct timeval ru_stime  System time used.

       The timeval structure shall be defined as described in <sys/time.h> .

       The  following  symbolic constants shall be defined as possible values for the resource argument of getrlimit() and setr-
       limit():

       RLIMIT_CORE
              Limit on size of core file.

       RLIMIT_CPU
              Limit on CPU time per process.

       RLIMIT_DATA
              Limit on data segment size.

       RLIMIT_FSIZE
              Limit on file size.

       RLIMIT_NOFILE
              Limit on number of open files.

       RLIMIT_STACK
              Limit on stack size.

       RLIMIT_AS
              Limit on address space size.


       The following shall be declared as functions and may also be defined as macros. Function prototypes shall be provided.


              int  getpriority(int, id_t);
              int  getrlimit(int, struct rlimit *);
              int  getrusage(int, struct rusage *);
              int  setpriority(int, id_t, int);
              int  setrlimit(int, const struct rlimit *);

       The id_t type shall be defined through typedef as described in <sys/types.h> .

       Inclusion of the <sys/resource.h> header may also make visible all symbols from <sys/time.h>.

       The following sections are informative.

APPLICATION USAGE
       None.

RATIONALE
       None.

FUTURE DIRECTIONS
       None.

SEE ALSO
       <sys/time.h>, <sys/types.h>, the System Interfaces volume  of  IEEE Std 1003.1-2001,  getpriority(),  getrusage(),  getr-
       limit()

COPYRIGHT
       Portions  of  this  text are reprinted and reproduced in electronic form from IEEE Std 1003.1, 2003 Edition, Standard for
       Information Technology -- Portable Operating System Interface (POSIX), The Open Group Base Specifications Issue 6,  Copy-
       right (C) 2001-2003 by the Institute of Electrical and Electronics Engineers, Inc and The Open Group. In the event of any
       discrepancy between this version and the original IEEE and The Open Group Standard, the original IEEE and The Open  Group
       Standard   is   the   referee   document.   The   original   Standard   can   be   obtained  online  at  http://www.open-
       group.org/unix/online.html .



IEEE/The Open Group                                           2003                                          <sys/resource.h>(0P)