home | help
STDBUF(1)		     General Commands Manual		       STDBUF(1)

NAME
     stdbuf -- change standard streams initial buffering

SYNOPSIS
     stdbuf [-e bufdef] [-i bufdef] [-o bufdef] [command [...]]

DESCRIPTION
     stdbuf  is used to change the initial buffering of standard input, standard
     output and/or standard error streams for command.	 It  relies  on  libstd-
     buf(3)  which  is loaded and configured by stdbuf through environment vari-
     ables.

     The options are as follows:

     -e bufdef
	     Set initial buffering of the standard error stream for  command  as
	     defined by bufdef (see "BUFFER DEFINITION").

     -i bufdef
	     Set  initial  buffering of the standard input stream for command as
	     defined by bufdef (see "BUFFER DEFINITION").

     -o bufdef
	     Set initial buffering of the standard output stream for command  as
	     defined by bufdef (see "BUFFER DEFINITION").

BUFFER DEFINITION
     Buffer definition is the same as in libstdbuf(3):

	   "0"	 unbuffered

	   "L"	 line buffered

	   "B"	 fully buffered with the default buffer size

	   size  fully	buffered  with a buffer of size bytes (suffixes 'k', 'M'
		 and 'G' are accepted)

EXAMPLES
     In the following example, the stdout stream of the awk(1) command	will  be
     fully  buffered by default because it does not refer to a terminal.  stdbuf
     is used to force it to be line-buffered  so  vmstat(8)'s  output  will  not
     stall until the full buffer fills.

	   # vmstat 1 | stdbuf -o L awk '$2 > 1 || $3 > 1' | cat -n

SEE ALSO
     libstdbuf(3), setvbuf(3)

HISTORY
     The stdbuf utility first appeared in FreeBSD 8.4.

AUTHORS
     The original idea of the stdbuf command comes from Padraig Brady who imple-
     mented it in the GNU coreutils.  Jeremie Le Hen implemented it on FreeBSD.

FreeBSD 9.1			 April 28, 2012 		       STDBUF(1)

home | help