DragonFly On-Line Manual Pages
STDBUF(1) DragonFly 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
libstdbuf(3) that is preloaded and configured by stdbuf through
environment variables.
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 '$NF > 1' | cat -n
SEE ALSO
libstdbuf(3), setvbuf(3)
HISTORY
The stdbuf utility first appeared in FreeBSD 8.4, and was imported to
DragonFly 5.9.
AUTHORS
The original idea of the stdbuf command comes from Padraig Brady who
implemented it in the GNU coreutils. Jeremie Le Hen implemented it on
FreeBSD.
DragonFly 5.9-DEVELOPMENT January 1, 2021 DragonFly 5.9-DEVELOPMENT