getrlimit()--Get resource limit

 #include <sys/resource.h>

 int getrlimit(int resource, struct rlimit *rlp); 

The getrlimit() function returns the resource limit for the specified resource. A resource limit is a way for the operating system to enforce a limit on a variety of resources used by a process. A resource limit is represented by a rlimit structure. The rlim_cur member specifies the current or soft limit and the rlim_max member specifies the maximum or hard limit.

The getrlimit() function supports the following resources:

The value of RLIM_INFINITY is considered to be larger than any other limit value. If the value of the limit is RLIM_INFINITY, then a limit is not enforced for that resource. The getrlimit() function always returns RLIM_INFINITY for the following resources: RLIMIT_AS, RLIMIT_CORE, RLIMIT_CPU, RLIMIT_DATA, and RLIMIT_STACK.

Parameters

resource

(Input)

The resource to get the limits for.

*rlp

(Output)

Pointer to a struct rlim_t where the values of the hard and soft limits are returned.

Authorities and Locks

None.

Return Value

Error Conditions

If getrlimit() is not successful, errno usually indicates one of the following errors. Under some conditions, errno could indicate an error other than those listed here.

[EFAULT]

The address used for an argument is not correct.

In attempting to use an argument in a call, the system detected an address that is not valid.

While attempting to access a parameter passed to this function, the system detected an address that is not valid.

[EINVAL]

An invalid parameter was found.

An invalid resource was specified.

Related Information

• The <sys/resource.h> file (see Header Files for UNIX-Type Functions)
  
  
• setrlimit()--Set resource limit
  
  
• ulimit()--Get and set process limits
  
  

Example

See Code disclaimer information for information pertaining to code examples.

#include <sys/resource.h>
#include <stdio.h>
#include <stdlib.h>
#include <errno.h>

int main (int argc, char *argv[])
{
  struct rlimit limit;
  
  /* Set the file size resource limit. */
  limit.rlim_cur = 65535;
  limit.rlim_max = 65535;
  if (setrlimit(RLIMIT_FSIZE, &limit) != 0) {
    printf("setrlimit() failed with errno=%d\n", errno);
    exit(1);
  }

  /* Get the file size resource limit. */
  if (getrlimit(RLIMIT_FSIZE, &limit) != 0) {
    printf("getrlimit() failed with errno=%d\n", errno);
    exit(1);
  }

  printf("The soft limit is %llu\n", limit.rlim_cur);
  printf("The hard limit is %llu\n", limit.rlim_max);
  exit(0);
}

The soft limit is 65535
The hard limit is 65535