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Full Discussion: sed internal working
Top Forums Shell Programming and Scripting sed internal working Post 302493984 by guruprasadpr on Friday 4th of February 2011 11:34:38 AM
Old 02-04-2011
sed internal working
Hi Experts
Say I have a huge text file. I want to add a header line to the file. We can get it done in many ways. One is using a temporary file, other way say using 'sed -i' which edits the file in-place. sed is always recommended for better performance. My question is: Internally sed also might be shifting all the lines one line below and inserting a new line at the top. Am I right? If so, how can the performance of sed be faster?

Guru
 

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LEARN ABOUT DEBIAN

fixnt

fixnt(1)							      Debian								  fixnt(1)

NAME

       fixnt - Filter for the Windows NT postscript printer driver.

SYNOPSIS

       fixnt < BADFILE.ps > GOODFILE.ps

DESCRIPTION

       The  Windows  NT  postscript  driver has a tendency to make broken postscript files, that are incompatible with psutils.  fixnt is a filter
       that fixes these problems, allowing the use of psnup(1).

       The filter takes the broken postscript file on stdin, and outputs a fixed postscript file on stdout.  It has no other form  for	invocation
       and takes no options on the command-line.

OPTIONS

       fixnt  takes no options.

BUGS

       fixnt does not check for NTPSOct94.  For a workaround, use a sed(1) command to replace 'NTPSOct94' with 'NTPSOct95', like so:
	      sed 's/NTPSOct94/NTPSOct95/g'
       This is particularly important for Windows NT 3.5 users.

AUTHOR

       fixnt   was   written   by   Holger   Bauer   <Holger.Bauer@topmail.de>,  Michael  Rath	<rath@itsm.uni-stuttgart.de>,  and  Akim  Demaille
       <demaille@inf.enst.fr>.

REPORTING BUGS

       Report bugs to the Authors, but avoid sending large postscript files.

       Patches are always welcome; send to <bauer@itsm.uni-stuttgart.de>.

SEE ALSO

       psnup(1), sed(1)

a2ps								   February 2003							  fixnt(1)
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