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ulimit(1)
NAME
  ulimit - Sets or reports a resource limit

SYNOPSIS
  ulimit [-HSacdfmnstvw] [limit]

STANDARDS
  Interfaces documented on this reference page conform to industry standards
  as follows:

  ulimit:  XPG4, XPG4-UNIX

  Refer to the standards(5) reference page for more information about
  industry standards and associated tags.

OPTIONS
  -H  [DIGITAL]	 The limits specified for the resources are hard limits.  A
      hard limit cannot be increased once it is set.

  -S  [DIGITAL]	 The limits specified for the resources are soft limits.  A
      soft limit can be increased up to the value of the hard limit.

  -a  [DIGITAL]	 Lists all of the current resource limits.  The limit operand
      is not permitted with this option.

  -c limit
      [DIGITAL]	 The limit operand specifies the number of 512-byte blocks
      for core dumps.

  -d limit
      [DIGITAL]	 The limit operand specifies the number of Kilobytes for the
      data area.

  -f limit
      The limit operand specifies the number of 512-byte blocks for files
      written by child processes (files of any size can be read).

  -m limit
      [DIGITAL]	 The limit operand specifies the number of Kilobytes for the
      size of physical memory.

  -n limit
      [DIGITAL]	 The limit operand specifies the number of file descriptors.

  -s limit
      [DIGITAL]	 The limit operand specifies the number of Kilobytes for the
      stack area.

  -t limit
      [DIGITAL]	 The limit operand specifies the number of seconds to be used
      by each process.

  -v limit
      [DIGITAL]	 The limit operand specifies the number of Kilobytes for
      virtual memory.  This option is supported only if RLIMIT_VMEM has been
      defined in /usr/include/sys/resource.h at compile-time.

  -w limit
      [DIGITAL]	 The limit operand specifies the number of Kilobytes for the
      swap area.  This option is supported only if RLIMIT_SWAP has been
      defined in /usr/include/sys/resource.h at compile-time.

OPERANDS
  limit
      If no options are specified, this is the number of 512 byte blocks to
      use as the new limit to file size. Otherwise, it is the limit applied
      to the resource indicatd by the option.

      [DIGITAL]	 This operand is not allowed with the -a option.

      If this operand is omitted, the current limit for the indicated
      resource is reported.

DESCRIPTION
  This command sets, or reports, the limit on the size of system resources,
  as indicated by the option.

  [DIGITAL]  If neither the -H option nor the -S option is specified, the
  limit applies to both hard and soft limits.  If only the -a option is
  specified, soft limits are reported.

  If there is no limit on a resource, the limit is reported as unlimited.

NOTES
  The ulimit command affects only the current execution environment,
  therefore it has no effect when run in a separate execution environment
  such as one of the following:

       nohup ulimit -f 10000
       env ulimit 10000

RESTRICTIONS
  Once a limit has been decreased, only a user with superuser privileges may
  increase it, even back to its original value.

EXIT STATUS
  The following exit values are returned:

  0   Successful completion.

  >0  A request for a higher limit was rejected or an error occurred.

EXAMPLES
   1.  To set the file size limit to 51,200 bytes, enter:
	    ulimit -f 100

   2.  To report the current file size limit, enter:
	    ulimit

   3.  The following example displays all current resource limits:
	    % ulimit -a

	    time(seconds)	 unlimited
	    file(blocks)	 unlimited
	    data(kbytes)	 131072
	    stack(kbytes)	 2048
	    memory(kbytes)	 84280
	    coredump(blocks)	 unlimited
	    nofiles(descriptors) 4096
	    vmemory(kbytes)	 1048576



ENVIRONMENT VARIABLES
  The following environment variables affect the execution of ulimit:

  LANG
      Provides a default value for the internationalization variables that
      are unset or null. If LANG is unset or null, the corresponding value
      from the default locale is used.	If any of the internationalization
      variables contain an invalid setting, the utility behaves as if none of
      the variables had been defined.

  LC_ALL
      If set to a non-empty string value, overrides the values of all the
      other internationalization variables.

  LC_CTYPE
      Determines the locale for the interpretation of sequences of bytes of
      text data as characters (for example, single-byte as opposed to
      multibyte characters in arguments).

  LC_MESSAGES
      Determines the locale for the format and contents of diagnostic
      messages written to standard error.

  NLSPATH
      Determines the location of message catalogues for the processing of
      LC_MESSAGES.

SEE ALSO
  Routines:  ulimit(3)

  Standards:  standards(5)