ulimit - Sets or reports a resource limit
ulimit [-HSacdfmnstvw] [limit]
Interfaces documented on this reference page conform to industry standards as follows:
ulimit: XPG4, XPG4-UNIX
Refer to the
reference page for more information
about industry standards and associated tags.
[Compaq] The limits specified for the resources are hard
limits. A hard limit cannot be increased once it is set.
[Compaq] The limits specified for the resources are soft
limits. A soft limit can be increased up to the value of the hard limit.
[Compaq] Lists all of the current resource limits. The
operand is not permitted with this option.
the number of 512-byte blocks for core dumps.
the number of Kilobytes for the data area.
operand specifies the
number of 512-byte blocks for files written by child processes (files of any
size can be read).
the number of Kilobytes for the size of physical memory.
the number of file descriptors.
the number of Kilobytes for the stack area.
the number of seconds to be used by each process.
the number of Kilobytes for virtual memory. This option is supported only
has been defined
the number of Kilobytes for the swap area. This option is supported only
has been defined
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.
This command sets, or reports, the limit on the size of system resources, as indicated by the option.
[Compaq] 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
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
Once a limit has been decreased, only a user with superuser privileges
may increase it, even back to its original value.
The following exit values are returned:
A request for a higher limit was rejected or an error occurred.
To set the file size limit to 51,200 bytes, enter: ulimit -f 100 To report the current file size limit, enter: ulimit 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
The following environment variables affect the execution of
Provides a default value for the internationalization variables
that are unset or null. If
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.
If set to a non-empty string value, overrides the values of
all the other internationalization variables.
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).
Determines the locale for the format and contents of diagnostic
messages written to standard error.
Determines the location of message catalogues for the processing