<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 con‐
stants 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 setrlimit():
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 sym‐
bols 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(), getrlimit()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, Copyright (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.opengroup.org/unix/online.html .
IEEE/The Open Group 2003 <sys/resource.h>(0P)
