NAME

ulimit − get and set user limits

SYNOPSIS

long ulimit (cmd, newlimit)
int cmd;
long newlimit;

DESCRIPTION

This function provides for control over process limits.  The cmd values available are:

1 Get the file size limit of the process.  The limit is in units of 512-byte blocks and is inherited by child processes.  Files of any size can be read. 

2 Set the file size limit of the process to the value of newlimit. Any process may decrease this limit, but only a process with an effective user ID of super-user may increase the limit.  Note that the limit must be specified in units of 512-byte blocks. 

3 Get the maximum possible break value.  See brk(2). Depending on system resources such as swap space, this maximum may not be attainable at a given time.

ERRORS

Ulimit will fail if one or more of the following conditions is true. 

­[EINVAL] cmd is not in the correct range. 

­[EPERM] Ulimit will fail and the limit will be unchanged if a process with an effective user ID other than super-user attempts to increase its file size limit. 

RETURN VALUE

Upon successful completion, a non-negative value is returned.  Errors return a -1, with errno set appropriately. 

SEE ALSO

brk(2), write(2). 

Hewlett-Packard Company  —  Version B.1,  May 11, 2021