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ulimit(3)
NAME
  ulimit - Set and gets process limits

SYNOPSIS
  #include <ulimit.h>

  long int ulimit(
	  int command,
	  ... );

LIBRARY
  Standard C Library (libc)

STANDARDS
  Interfaces documented on this reference page conform to industry standards
  as follows:

  ulimit():  XSH4.2

  Refer to the standards(5) reference page for more information about
  industry standards and associated tags.

PARAMETERS
  command
      Specifies the form of control. The command parameter can have the
      following values:

  UL_GETFSIZE
      Returns the soft file size limit of the process. The limit is reported
      in 512-byte blocks (see the sys/param.h file) and is inherited by child
      processes.  The function can read files of any size.

      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
      Sets the hard and soft process file size limit for output operations to
      the value of the second parameter, taken as a long int value, and
      returns the new file size limit. Any process can decrease its own hard
      limit, but only a process with the privileges can increase the limit.

      The hard and soft file size limits are set to the specified value
      multiplied by 512. If the result would overflow an rlim_t, the actual
      value set is unspecified.

  UL_GETBREAK
      [Tru64 UNIX]  Returns the maximum possible break value as described in
      the brk(2) reference page.

DESCRIPTION
  The ulimit() function controls process limits.

  During access to remote files, the process limits of the local node are
  used.

NOTES
  The ulimit() function is implemented with calls to setrlimit(). The two
  interfaces should not be used in the same program.  The result of doing so
  is undefined.

RETURN VALUES
  Upon successful completion, ulimit() returns the value of the requested
  limit and does not change the setting of errno. Otherwise, a value of -1 is
  returned, and errno is set to indicate the error.

ERRORS
  If the ulimit() function fails, the limit remains unchanged and errno is
  set to one of the following values:

  [EINVAL]
      The command parameter is invalid.

  [EPERM]
      A process without appropriate system privileges attempted to increase
      its file size limit.

  As all return values are permissable 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
  nonzero.

SEE ALSO
  Commands: ulimit(1)

  Functions: brk(2), getrlimit(2), write(2)

  Routines: pathconf(2)

  Standards: standards(5)

Index for Section 3

Alphabetical listing for U

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