ulimit(2) - osol9

1ulimit(2)                        System Calls                        ulimit(2)
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NAME

6       ulimit - get and set process limits
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SYNOPSIS

9       #include <ulimit.h>
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11       long ulimit(int cmd, /* newlimit */...);
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DESCRIPTION

15       The  ulimit()  function provides for control over process limits. It is
16       effective in limiting the growth of regular files. Pipes are limited to
17       PIPE_MAX bytes.
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20       The cmd values, defined in <ulimit.h>, include:
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22       UL_GETFSIZE    Return  the  soft  file  size  limit of the process. The
23                      limit is in units of 512-byte blocks and is inherited by
24                      child  processes.  Files  of  any  size can be read. The
25                      return value is the integer part of the soft  file  size
26                      limit  divided  by  512.  If the result cannot be repre‐
27                      sented as a long int, the result is unspecified.
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30       UL_SETFSIZE    Set the hard and soft file size limits for output opera‐
31                      tions  of  the  process to the value of the second argu‐
32                      ment, taken as a long int. Any process may decrease  its
33                      own  hard  limit,  but  only  a process with appropriate
34                      privileges may increase the limit.  The  new  file  size
35                      limit  is  returned.  The hard and soft file size limits
36                      are set to the specified value multiplied  by  512.   If
37                      the  result would overflow an rlimit_t, the actual value
38                      set is unspecified.
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41       UL_GMEMLIM     Get the maximum possible break value (see brk(2)).
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44       UL_GDESLIM     Get the current value of  the  maximum  number  of  open
45                      files per process configured in the system.
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RETURN VALUES

49       Upon successful completion, ulimit() returns the value of the requested
50       limit.  Otherwise, −1 is returned, the limit is not changed, and  errno
51       is set to indicate the error.
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ERRORS

54       The ulimit() function will fail if:
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56       EINVAL    The cmd argument is not valid.
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59       EPERM     A  process  that  has not asserted {PRIV_SYS_RESOURCE} in its
60                 effective set is trying to increase its file size limit.
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USAGE

64       Since all return values are permissible in a successful  situation,  an
65       application  wishing  to check for error situations should set errno to
66       0, then call ulimit(), and if it returns −1, check  if  errno  is  non-
67       zero.
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70       The getrlimit() and setrlimit() functions provide a more general inter‐
71       face for controlling process limits, and are preferred  over  ulimit().
72       See getrlimit(2).
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ATTRIBUTES

75       See attributes(5) for descriptions of the following attributes:
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80       ┌─────────────────────────────┬─────────────────────────────┐
81       │      ATTRIBUTE TYPE         │      ATTRIBUTE VALUE        │
82       ├─────────────────────────────┼─────────────────────────────┤
83       │Interface Stability          │Standard                     │
84       └─────────────────────────────┴─────────────────────────────┘
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