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changing col(1) command stdout as fully buffered?

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Operating Systems HP-UX changing col(1) command stdout as fully buffered?
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Old 06-09-2006
changing col(1) command stdout as fully buffered?
Hi All,

I am talking about unix col(1) command used for some reverse line filtering etc.
And I notice that the stdout of this command is line buffered i.e. the stdout will flush the data in its buffer line by line. So the number of writes performed by stdout are more.

So now if I make stdout as fully buffered it will reduce the write hits. Smilie

But if I do these changes I think there will some problems
-> when slow terminals use col(1) as command , then the turn around time will get reduce for it self.
eg: cat file | col -b | lp
Here lp will receive data in terms of buffer size but before it was receving in terms of each lines.

So can I change change col(1) command's stdout to fully buffered?

So do any of you know some more problems related with this change , and can I see some link about col(1) command design stating that it should be either line buffered or fully buffered etc.


Waiting for positive replay,
Sunil kumar.
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LEARN ABOUT FREEBSD

libstdbuf

LIBSTDBUF(3)						   BSD Library Functions Manual 					      LIBSTDBUF(3)

NAME

     libstdbuf -- preloaded library to change standard streams initial buffering

DESCRIPTION

     The libstdbuf library is meant to be preloaded with the LD_PRELOAD environment variable to as to change the initial buffering of standard
     input, standard output and standard error streams.

     Although you may load and configure this library manually, an utility, stdbuf(1), can be used to run a command with the appropriate environ-
     ment variables.

ENVIRONMENT

     Each stream can be configured independently through the following environment variables (values are defined below):

	   _STDBUF_I
		 Initial buffering definition for the standard input stream

	   _STDBUF_O
		 Initial buffering definition for the standard output stream

	   _STDBUF_E
		 Initial buffering definition for the standard error stream

     Each variable may take one of the following values:

	   "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)

EXAMPLE

     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.
     libstdbuf is used to force it to be line-buffered so vmstat(8)'s output will not stall until the full buffer fills.

	   # vmstat 1 | LD_PRELOAD=/usr/lib/libstdbuf.so 
	       STDBUF_1=L awk '$2 > 1 || $3 > 1' | cat -n

     See also the manpage of stdbuf(1) for a simpler way to do this.

HISTORY

     The libstdbuf library first appeared in FreeBSD 8.4.

AUTHORS

     The original idea of the libstdbuf command comes from Padraig Brady who implemented it in the GNU coreutils.  Jeremie Le Hen implemented it
     on FreeBSD.

BSD
								  April 28, 2012							       BSD