topic Re: Read in Operating System - HP-UX

Read

Vanquish — Mon, 03 May 2004 12:43:24 GMT

Hi
I need to read the first line of the file and the last line of the file.
can i use head or tail for doing that?
Thanks

Re: Read

Dave La Mar — Mon, 03 May 2004 12:50:11 GMT

Certainly.
head -1 your_file > some_new_file
tail -1 your_file >> some_new_file

Best regards,

dl

Re: Read

A. Clay Stephenson — Mon, 03 May 2004 12:56:27 GMT

The tail command can be used for both but if all you want to do is read the 1st line of a file, the line command is perfect

INFILE=myfile
FIRST=$(line < ${INFILE})
LAST=$(tail -n -1 ${INFILE})

echo "First: ${FIRST}"
echo "Last : ${LAST}"

Re: Read

Rodney Hills — Mon, 03 May 2004 13:19:51 GMT

You could use the sed command.

set -A data `sed -ne '1p;$p' echo First line is ${data[0]}
echo Last line is ${data[1]}

HTH

-- Rod Hills

Re: Read

Rodney Hills — Mon, 03 May 2004 13:24:10 GMT

Oh, be sure to put the following in the script before the "sed"-

IFS="^J"

^J is what you get when you press control-v followed by CR.

HTH

-- Rod Hills

Re: Read

Thom Cornwell — Mon, 03 May 2004 13:48:25 GMT

sed -n '1p;$p' input-file-name

Re: Read

Hein van den Heuvel — Tue, 04 May 2004 00:07:27 GMT

I like the sed solutions.

Here is a simple awk solution in case you need to do more then just print:

awk 'BEGIN {getline; print} END {print x} {x=$0}' < your-file

And a silly solution in perl:

$ perl -e 'while (<>) {print unless ($x); $x=$_} print $x' < your-file

- loop through the input, print the line uless you have remembered a line. This takes care of the first line. Remembering lines in $x. At the end, print the last line remembered... being the last line :-).

Re: Read

KapilRaj — Tue, 04 May 2004 04:12:58 GMT

echo "`head -1 yourfile` "\\n" `tail -1 yourfile` "

regds,

Kaps