read the input file from the specified line no till end

suchi_s · 09-09-2004, 01:07 AM

save the file from specified line nu till end

druuna · 09-09-2004, 02:34 AM

This is one way of doing that:

sed '25,$p' infile > outfile

Change 25 to whatever line you want/need.

Hope this helps.

suchi_s · 09-09-2004, 03:45 AM

what if value 25 is stored in a variable

druuna · 09-09-2004, 03:49 AM

Just answered this a day ago, but here it is:

FIRST=25
sed -n '${FIRST},$p' infile > outfile

If used inside a script you might need to replace the single quotes by double quotes.

suchi_s · 09-09-2004, 03:53 AM

it worked
thanks a lot
can u clear why inside the script to use doublee quotes and outside single..
i m not clear with it

druuna · 09-09-2004, 04:36 AM

This has to do with (command) line expansion, which is not something that can be explained in a few sentences.

In short:

Without the double quotes there will be no expansion. In this case ${FIRST} will not be replaced by the value that this variable holds.

Take a look at the bash manpage for more detail, especially this section: EXPANSION.