truncate(2)							System Calls Manual						       truncate(2)

NAME

       ftruncate, truncate - truncate a file to a specified length

SYNOPSIS

DESCRIPTION

       The function causes the regular file referenced by fildes to have a size of length bytes.

       The function causes the regular file named by path to have a size of length bytes.

       The  effect of and on other types of files is unspecified. If the file previously was larger than length, the extra data is lost. If it was
       previously shorter than length, bytes between the old and new lengths are read as zeroes. With the file must be open for writing;  for  the
       process must have write permission for the file.

       If  the	request would cause the file size to exceed the soft file size limit for the process, the request will fail and the implementation
       will generate the signal for the process.

       These functions do not modify the file offset for any open file descriptions associated with the file.  On successful  completion,  if  the
       file size is changed, these functions will mark for update the st_ctime and st_mtime fields of the file, and if the file is a regular file,
       the and bits of the file mode may be cleared.

RETURN VALUE

       Upon successful completion, returns 0. Otherwise a -1 is returned, and is set to indicate the error.

ERRORS

       If or fails, is set to one of the following values:

	      A signal was caught during execution.

	      The		     length argument was less than 0.

	      [EFBIG] or [EINVAL]    The length argument was greater than the maximum file size.

	      An I/O error occurred while reading from or writing to a file system.

	      Enforcement mode file/record locking is set (see
				     chmod(2)), and there are outstanding record locks on the file with the or system calls.

       If fails, is set to one of the following values:

	      [EBADF] or [EINVAL]    The fildes argument is not a file descriptor open for writing.

	      The user's disk quota block limit has been reached for this file system.

	      The		     fildes argument references a file that was opened without write permission.

       If fails, is set to one of the following values:

	      A component of the     path prefix denies search permission, or write permission is denied on the file.

	      The user's disk quota block limit has been reached for this file system.

	      path		     points outside the process's allocated address space. The reliable detection of this error is  implementation
				     dependent.

	      The named file is a directory.

	      Too many symbolic links were encountered in resolving
				     path.

	      Pathname resolution produced an intermediate result
				     whose length exceeds bytes, or the length of a component of the pathname exceeds bytes.

	      A component of	     does not name an existing file or path is an empty string.

	      A component of the     path prefix of path is not a directory.

	      The named file resides on a read-only file system.

	      The file is a pure procedure (shared text) file that is being executed.

AUTHOR

       was developed by the University of California, Berkeley.

SEE ALSO

       chmod(2), fcntl(2), flock(2), ftruncate64(2), lockf(2), open(2), truncate64(2), privileges(5), <unistd.h>.

CHANGE HISTORY

       First released in Issue 4, Version 2.

STANDARDS CONFORMANCE

       truncate(): AES ftruncate(): AES, SVID3

																       truncate(2)