Name

ulimit

Synopsis

    ulimit [options] [n]

Print the value of one or more resource limits, or, if n is specified, set a resource limit to n. Resource limits can be either hard (-H) or soft (-S). By default, ulimit sets both limits or prints the soft limit. The options determine which resource is acted on.

Options

-H

Hard limit. Anyone can lower a hard limit; only privileged users can raise it.

-S

Soft limit. Must be less than or equal to the hard limit.

-a

Print all limits.

-b

Size of socket buffers. ksh93 only.

-c

Maximum size of core files.

-d

Maximum kilobytes of data segment or heap.

-f

Maximum size of files (the default option).

-l

Maximum size of address space that can be locked in memory. Not ksh88.

-L

Maximum number of file locks. ksh93 only.

-m

Maximum kilobytes of physical memory. (Not effective on all Unix systems.)

-M

Maximum size of the address space. ksh93 only.

-n

Maximum number of file descriptors.

-p

Size of pipe buffers. (Not effective on all Unix systems.)

-s

Maximum kilobytes of stack segment.

-t

Maximum CPU seconds.

-T

Maximum number of threads. ksh93 only.

-u

Maximum number of processes a single user can have.

-v

Maximum kilobytes of virtual memory.

Get Unix in a Nutshell, 4th Edition now with the O’Reilly learning platform.

O’Reilly members experience books, live events, courses curated by job role, and more from O’Reilly and nearly 200 top publishers.