Sponsored Content
Top Forums Shell Programming and Scripting Scratching my head over old post Post 303003142 by OMLEELA on Friday 8th of September 2017 03:38:02 AM
Old 09-08-2017
Scratching my head over old post

Hello !

Pondering over some old post & I need some help.

Here is the link below -

When I run this,

Code:
echo " process(130) Deleting Text on line 11 (ESN:27723211621B01DJ68AG) because a number wasnt 'AVAILABLE'  and is not found in the database" | awk '$0=$2' FS=\( RS=\) "

I get the following output
Code:
130 
ESN:27723211621B01DJ68AG

Next,

Code:
echo " process(130) :27723211621B01DJ68AG) because a number wasnt 'AVAILABLE'  and is not found in the database" | sed "s/^.*(\([^)]*\)).*(....\(.*\)).*'\(.*\)'.*/\1 \2 \3/"

130 27723211621B01DJ68AG AVAILABLE

Questions -
1. In there , the magic is happening all because of $0=$2. Can someone please explain to me as to what does $0=$2 means ?
2. Also can someone go over the sed operation here as I tried to understand this for the past 2 hours and I am not getting anywhere with this.


best regards,
Lee.
 

9 More Discussions You Might Find Interesting

1. UNIX for Dummies Questions & Answers

help.. I am in way over my head !!!!

my boss has done it again I have been sent to fix a unix issue and I ma hoping you can help three issues 1st. I have a printer that when you try to print to it the print job comes out on a diffrent printer. If I take the printer ( dot matrix thourgh a serail connection) to a diffrent local the... (3 Replies)
Discussion started by: oberon42
3 Replies

2. UNIX for Dummies Questions & Answers

head & tail

I've a major file which includes other files and now I wanna 'cut' the file in several minor parts....like .... find / -name "*.tmp" >filea wc -l filea >fileb sed -e '1s/ filea//' fileb >filec AMOUNT=`cat filec` if ; then cat file a |head -100l (ell) |tail -100l >filec cat file a |head... (6 Replies)
Discussion started by: svennie
6 Replies

3. Shell Programming and Scripting

head command

Hi All, How can the head command be used to extract only a particular line. By default head -n filename displays the first n lines. I want only the nth line. I couldn't get it from forum search. Thanks, Sumesh (6 Replies)
Discussion started by: sumesh.abraham
6 Replies

4. Shell Programming and Scripting

Head and Tail in One Line

I am new to UNIX......I have one file which contains thousnads of records with header and tailer. Header Record 1 Record 2 .... .... Last Record Trailer I want to concatenate Header and Trailer in the first line....now the output should look like this: Header: Header value, Trailer:... (2 Replies)
Discussion started by: 33junaid
2 Replies

5. Shell Programming and Scripting

head usage

$ct=1 head -n $ct file. When i used like this, i got an error , Bad usage of head Cant we use variables in place of number in HEAD. In my requirement for every iteration i should increase the number in Head and tail the last one. HOw can i achieve this (5 Replies)
Discussion started by: vasuarjula
5 Replies

6. Shell Programming and Scripting

Search HEAD of CVS

Im looking for a 'relatively' easy way to search through cvs to look for a particular string in the HEAD revisions. I realize the way CVS stores versions makes this difficult. But I'm trying to come up with some script to allow this search (performance is not expected here). Currently this... (0 Replies)
Discussion started by: bobtheowl2
0 Replies

7. Shell Programming and Scripting

head followed by variable??

I know that the common use of head is for example head -3 etc.Is there any possibility that,if i have a variable that equals to an integer(i=5),i can write head -i?? If not,what syntax or commands should i write down in order to have the same result? //maybe something lik head -"$variable" ? (2 Replies)
Discussion started by: bashuser2
2 Replies

8. UNIX for Dummies Questions & Answers

find and head -1

i have lots of files in /law/prod and /law/dev, such as AP20PD, AP20WS, AP20.scr, AP20.rpt if i am in /law DIR find . -name AP20PD, found in /law/prod and /law/dev i want to head -1 AP20PD from both location and >> /tmp/test.log can i use find and head in one line ? ----------... (1 Reply)
Discussion started by: tjmannonline
1 Replies

9. Shell Programming and Scripting

Diff/head - not sure if this is the right command to use

Hi, I need some advise on whether there is a better way of doing what I am currently planning to do. Perhaps I should be using arrays instead of re-directing output to files? I need to use a tool/program named ADRCI provided by Oracle to remove trace files that it generates. Honestly it is... (1 Reply)
Discussion started by: newbie_01
1 Replies
SHELL-QUOTE(1p) 					User Contributed Perl Documentation					   SHELL-QUOTE(1p)

NAME
shell-quote - quote arguments for safe use, unmodified in a shell command SYNOPSIS
shell-quote [switch]... arg... DESCRIPTION
shell-quote lets you pass arbitrary strings through the shell so that they won't be changed by the shell. This lets you process commands or files with embedded white space or shell globbing characters safely. Here are a few examples. EXAMPLES
ssh preserving args When running a remote command with ssh, ssh doesn't preserve the separate arguments it receives. It just joins them with spaces and passes them to "$SHELL -c". This doesn't work as intended: ssh host touch 'hi there' # fails It creates 2 files, hi and there. Instead, do this: cmd=`shell-quote touch 'hi there'` ssh host "$cmd" This gives you just 1 file, hi there. process find output It's not ordinarily possible to process an arbitrary list of files output by find with a shell script. Anything you put in $IFS to split up the output could legitimately be in a file's name. Here's how you can do it using shell-quote: eval set -- `find -type f -print0 | xargs -0 shell-quote --` debug shell scripts shell-quote is better than echo for debugging shell scripts. debug() { [ -z "$debug" ] || shell-quote "debug:" "$@" } With echo you can't tell the difference between "debug 'foo bar'" and "debug foo bar", but with shell-quote you can. save a command for later shell-quote can be used to build up a shell command to run later. Say you want the user to be able to give you switches for a command you're going to run. If you don't want the switches to be re-evaluated by the shell (which is usually a good idea, else there are things the user can't pass through), you can do something like this: user_switches= while [ $# != 0 ] do case x$1 in x--pass-through) [ $# -gt 1 ] || die "need an argument for $1" user_switches="$user_switches "`shell-quote -- "$2"` shift;; # process other switches esac shift done # later eval "shell-quote some-command $user_switches my args" OPTIONS
--debug Turn debugging on. --help Show the usage message and die. --version Show the version number and exit. AVAILABILITY
The code is licensed under the GNU GPL. Check http://www.argon.org/~roderick/ or CPAN for updated versions. AUTHOR
Roderick Schertler <roderick@argon.org> perl v5.8.4 2005-05-03 SHELL-QUOTE(1p)
All times are GMT -4. The time now is 11:10 PM.
Unix & Linux Forums Content Copyright 1993-2022. All Rights Reserved.
Privacy Policy