/** @file ../include/sys/resource.h

 @internalComponent

 */

 /** @fn  getpriority(int which, int who)

 @param which

 @param who

 Note: This description also covers the following functions -

  setpriority() 

 @return   Since getpriority can legitimately return the value -1, it is necessary

 to clear the external variable errno prior to the

 call, then check it afterward to determine

 if a -1 is an error or a legitimate value. The setpriority returns 0 on success and -1 on error with the errno set.

   The scheduling

 priority of the process, process group, or user, as indicated by which and who is obtained with the getpriority system call and set with the setpriority system call.

 The which argument

 is one of PRIO_PROCESS, PRIO_PGRP, or PRIO_USER, and who is interpreted relative to which (a process identifier for PRIO_PROCESS, process group

 identifier for PRIO_PGRP, and a user ID for PRIO_USER ). A zero value of who denotes the current process, process group, or user.

 The prio argument

 is a value in the range -20 to 20.

 The default priority is 0;

 lower priorities cause more favorable scheduling.

  If the prio is greater than the greatest priority supported, it is set to the greatest priority supported.

 If the prio is lesser than the least priority supported, it is set to the least priority supported.

 Examples:

 @code

 #include<sys/resource.h>        

 #include<unistd.h>

 #include<stdio.h>

 int test_getpriority()

 {

    int retVal;

    errno = 0;

    retVal = getpriority(PRIO_PROCESS, 0);

    if((retVal == -1) && (errno == ENOSYS))

    {

       printf("Failed");

       return -1;

    }

    else

    {

       printf("getpriority passed");

       printf("

 priority = %d ", retVal);

    }    

    return 0;

 }

 @endcode

  Output

 @code

 getpriority passed

 priority = 0

 @endcode

 @code

 #include<sys/resource.h>        

 #include<unistd.h>

 #include<stdio.h>

 int test_setpriority()

 {

    int retVal;

    errno = 0;

    retVal = setpriority(PRIO_PROCESS, 0, 0);

    if((retVal == -1) && (errno == ENOSYS))

    {

       printf("Failed");

       return -1;

    }

    else

    {

       printf("Setpriority passed");

       printf(" getpriority now: %d", getpriority(PRIO_PROCESS,0))

     }   

    return 0;

 }

 @endcode

  Output

 @code

 Setpriority passed

 getpriority now: 0

 @endcode

 Limitations:

 1. The values PRIO_PGRP and PRIO_USER for the which and any value other than 0 for who are not supported, when given return ENOSYS. 

 2. To effectively increase or decrease the priority of the process, one should consider the following:  

 Highest                                                                 -16 to -20         Above Normal                                                     -6 to -15         Normal                                                                          +4 to -5         Below Normal                                                    +14 to +5         Lowest                                                                    +20 to +15 3. 

 The setting of the priority to values -16 to -20 is not supported, the use of which sets errno to EINVAL.

 @see nice()

 @publishedAll

 @externallyDefinedApi

 */

 /** @fn  setpriority(int which, int who, int value)

 @param which

 @param who

 @param value

 Refer to  getpriority() for the documentation

 @see nice()

 @publishedAll

 @externallyDefinedApi

 */

 /** @struct rlimit

 Contains the following members,

 @publishedAll

 @externallyDefinedApi

 */

 /** @var rlimit::rlim_cur

 current (soft) limit

 */

 /** @var rlimit::rlim_max

 maximum value for rlim_cur

 */

 /** @struct rusage 

 Contains the following members,

 @publishedAll

 @externallyDefinedApi

 */

 /** @var rusage::ru_utime

 user time used

 */

 /** @var rusage::ru_stime

 system time used

 */

 /** @var rusage::ru_maxrss

 max resident set size

 */

 /** @var rusage::ru_ixrss

 integral shared memory size

 */

 /** @var rusage::ru_idrss

 integral unshared data

 */

 /** @var rusage::ru_isrss

 integral unshared stack

 */

 /** @var rusage::ru_minflt

 page reclaims

 */

 /** @var rusage::ru_majflt

 page faults

 */

 /** @var rusage::ru_nswap

 (c + j) swaps

 */

 /** @var rusage::ru_inblock

 block input operations

 */

 /** @var rusage::ru_oublock

 block output operations

 */

 /** @var rusage::ru_msgsnd

 messages sent

 */

 /** @var rusage::ru_msgrcv

  messages received 

 */

 /** @var rusage::ru_nsignals

 signals received

 */

 /** @var rusage::ru_nvcsw

 voluntary context switches

 */

 /** @var rusage::ru_nivcsw

 involuntary

 */

 /** @typedef typedef	__rlim_t	rlim_t

 Unsigned integer type used for limit values.

 @publishedAll

 @externallyDefinedApi

 */

 /** @def RLIM_INFINITY

 unsigned long int

 @publishedAll

 @externallyDefinedApi

 */

 /** @def RLIMIT_CORE

 core file size 

 @publishedAll

 @externallyDefinedApi

 */

 /** @def RLIMIT_CPU

 cpu time in milliseconds

 @publishedAll

 @externallyDefinedApi

 */

 /** @def RLIMIT_DATA

 data size

 @publishedAll

 @externallyDefinedApi

 */

 /** @def RLIMIT_FSIZE

 maximum file size

 @publishedAll

 @externallyDefinedApi

 */

 /** @def RLIMIT_NOFILE

 number of open files

 @publishedAll

 @externallyDefinedApi

 */

 /** @def RLIMIT_STACK

 stack size

 @publishedAll

 @externallyDefinedApi

 */

 /** @def RLIMIT_AS

 standard name for RLIMIT_VMEM

 @publishedAll

 @externallyDefinedApi

 */

 /** @def RUSAGE_SELF

 Resource utilization information.

 @publishedAll

 @externallyDefinedApi

 */

 /** @def RUSAGE_CHILDREN

 Resource utilization information.

 @publishedAll

 @externallyDefinedApi

 */

 /** @def PRIO_PROCESS

 Process priority specifications to get or set priority.

 @publishedAll

 @externallyDefinedApi

 */

 /** @def PRIO_PGRP

 Process priority specifications to get or set priority.

 @publishedAll

 @externallyDefinedApi

 */

 /** @def PRIO_USER

 Process priority specifications to get or set priority.

 @publishedAll

 @externallyDefinedApi

 */