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ulimit(3) [netbsd man page]

ULIMIT(3)						   BSD Library Functions Manual 						 ULIMIT(3)

NAME
ulimit -- get and set process limits LIBRARY
Standard C Library (libc, -lc) SYNOPSIS
#include <ulimit.h> long int ulimit(int cmd, ...); DESCRIPTION
The ulimit() function provides a method to query or alter resource limits of the calling process. The method to be performed is specified by the cmd argument; possible values are: UL_GETFSIZE Return the soft file size limit of the process. The value returned is in units of 512-byte blocks. If the result cannot be represented in an object of type long int, the result is unspecified. UL_SETFSIZE Set the hard and soft file size limits of the process to the value of the second argument passed, which is in units of 512-byte blocks, and which is expected to be of type long int. The new file size limit of the process is returned. Any process may decrease the limit, but raising it is only permitted if the caller is the super-user. If successful, the ulimit() function will not change the setting of errno. RETURN VALUES
If successful, the ulimit() function returns the value of the requested limit. Otherwise, it returns -1, sets errno to indicate an error, and the limit is not changed. Therefore, to detect an error condition applications should set errno to 0, call ulimit(), and check if -1 is returned and errno is non-zero. ERRORS
The ulimit() function will fail if: [EINVAL] The cmd argument is not valid. [EPERM] It was attempted to increase a limit, and the caller is not the super-user. SEE ALSO
getrlimit(2), setrlimit(2) STANDARDS
The ulimit() function conforms to X/Open System Interfaces and Headers Issue 5 (``XSH5'') and IEEE Std 1003.1-2001 (``POSIX.1''). It was marked as obsolete in the IEEE Std 1003.1-2008 (``POSIX.1'') revision, which recommended the use of getrlimit(2) and setrlimit(2) instead, noting that because ulimit() uses the type long rather than rlim_t, it may not be sufficient for file sizes on many current systems. BSD
April 30, 2010 BSD

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ulimit(2)							   System Calls 							 ulimit(2)

NAME
ulimit - get and set process limits SYNOPSIS
#include <ulimit.h> long ulimit(int cmd, /* newlimit */...); DESCRIPTION
The ulimit() function provides for control over process limits. It is effective in limiting the growth of regular files. Pipes are limited to PIPE_MAX bytes. The cmd values, defined in <ulimit.h>, include: UL_GETFSIZE Return the soft file size limit of the process. The limit is in units of 512-byte blocks and is inherited by child pro- cesses. Files of any size can be read. The return value is the integer part of the soft file size limit divided by 512. If the result cannot be represented as a long int, the result is unspecified. UL_SETFSIZE Set the hard and soft file size limits for output operations of the process to the value of the second argument, taken as a long int. Any process may decrease its own hard limit, but only a process with appropriate privileges may increase the limit. The new file size limit is returned. The hard and soft file size limits are set to the specified value multiplied by 512. If the result would overflow an rlimit_t, the actual value set is unspecified. UL_GMEMLIM Get the maximum possible break value (see brk(2)). UL_GDESLIM Get the current value of the maximum number of open files per process configured in the system. RETURN VALUES
Upon successful completion, ulimit() returns the value of the requested limit. Otherwise, -1 is returned, the limit is not changed, and errno is set to indicate the error. ERRORS
The ulimit() function will fail if: EINVAL The cmd argument is not valid. EPERM A process that has not asserted {PRIV_SYS_RESOURCE} in its effective set is trying to increase its file size limit. USAGE
Since all return values are permissible in a successful situation, an application wishing to check for error situations should set errno to 0, then call ulimit(), and if it returns -1, check if errno is non-zero. The getrlimit() and setrlimit() functions provide a more general interface for controlling process limits, and are preferred over ulimit(). See getrlimit(2). ATTRIBUTES
See attributes(5) for descriptions of the following attributes: +-----------------------------+-----------------------------+ | ATTRIBUTE TYPE | ATTRIBUTE VALUE | +-----------------------------+-----------------------------+ |Interface Stability |Standard | +-----------------------------+-----------------------------+ SEE ALSO
brk(2), getrlimit(2), write(2), attributes(5), privileges(5), standards(5) SunOS 5.11 1 Feb 2003 ulimit(2)
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