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ulimit(2) [opensolaris man page]

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)

Check Out this Related Man Page

ULIMIT(3P)						     POSIX Programmer's Manual							ULIMIT(3P)

PROLOG
This manual page is part of the POSIX Programmer's Manual. The Linux implementation of this interface may differ (consult the correspond- ing Linux manual page for details of Linux behavior), or the interface may not be implemented on Linux. NAME
ulimit -- get and set process limits SYNOPSIS
#include <ulimit.h> long ulimit(int cmd, ...); DESCRIPTION
The ulimit() function shall control process limits. The process limits that can be controlled by this function include the maximum size of a single file that can be written (this is equivalent to using setrlimit() with RLIMIT_FSIZE). The cmd values, defined in <ulimit.h>, include: UL_GETFSIZE Return the file size limit (RLIMIT_FSIZE) of the process. The limit shall be in units of 512-byte blocks and shall be inherited by child processes. Files of any size can be read. The return value shall be the integer part of the soft file size limit divided by 512. If the result cannot be represented as a long, the result is unspecified. UL_SETFSIZE Set the file size limit for output operations of the process to the value of the second argument, taken as a long, multiplied by 512. If the result would overflow an rlim_t, the actual value set is unspecified. Any process may decrease its own limit, but only a process with appropriate privileges may increase the limit. The return value shall be the integer part of the new file size limit divided by 512. The ulimit() function shall not change the setting of errno if successful. As 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 to see if errno is non-zero. RETURN VALUE
Upon successful completion, ulimit() shall return the value of the requested limit. Otherwise, -1 shall be returned and errno set to indi- cate the error. ERRORS
The ulimit() function shall fail and the limit shall be unchanged if: EINVAL The cmd argument is not valid. EPERM A process not having appropriate privileges attempts to increase its file size limit. The following sections are informative. EXAMPLES
None. APPLICATION USAGE
Since the ulimit() function uses type long rather than rlim_t, this function is not sufficient for file sizes on many current systems. Applications should use the getrlimit() or setrlimit() functions instead of the obsolescent ulimit() function. RATIONALE
None. FUTURE DIRECTIONS
The ulimit() function may be removed in a future version. SEE ALSO
exec, getrlimit(), write() The Base Definitions volume of POSIX.1-2008, <ulimit.h> COPYRIGHT
Portions of this text are reprinted and reproduced in electronic form from IEEE Std 1003.1, 2013 Edition, Standard for Information Technol- ogy -- Portable Operating System Interface (POSIX), The Open Group Base Specifications Issue 7, Copyright (C) 2013 by the Institute of Electrical and Electronics Engineers, Inc and The Open Group. (This is POSIX.1-2008 with the 2013 Technical Corrigendum 1 applied.) In the event of any discrepancy between this version and the original IEEE and The Open Group Standard, the original IEEE and The Open Group Stan- dard is the referee document. The original Standard can be obtained online at http://www.unix.org/online.html . Any typographical or formatting errors that appear in this page are most likely to have been introduced during the conversion of the source files to man page format. To report such errors, see https://www.kernel.org/doc/man-pages/reporting_bugs.html . IEEE
/The Open Group 2013 ULIMIT(3P)
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