So I'm going to explain what I think is happening, and someone can correct me if I'm wrong so I can learn here.
Once it reads through all the variables and stores what it finds, it gets to the if(i==NF) and that tells it that it's done and to print out what it has stored.
Then it sets all of the variables back to empty so they can be used again the next run without returning old information.
One question on this: /.*=|\/.*/
I'm guessing that .*= means pick up anything before the equal sign and remove it.
What does the other side of that do? What does the |\/.* do?
I know that the \ is an excape character, so does it find anything after a / and remove it?
Hi All,
I have been working on awk and arrays. I have this small script:
cat maillog*|awk -F: '$2=="SMTP-Accept" && $5~/string/ {lastdate=substr($1,1,8); internaluser=$5; v++} END {for (j in v) {print lastdate, v, j}'| sort>> mail.list
This gives me the number of mails users are getting. ... (1 Reply)
Been struggling with a problem, I have been trying to do this in awk, but am unable to figure this out, I think arrays have to be used, but unsure how to accomplish this.
I have a input file that looks like this:
141;ny;y;g
789;ct;e;e
23;ny;n;u
45;nj;e;u
216;ny;y;u
7;ny;e;e
1456;ny;e;g... (3 Replies)
Guys,
OK so i have been trying figure this all all day, i guess its a pretty easy way to do it.
Right, so i have to column of data which i have gotten from one huge piece of data. What i would like to do is to put both of these into one array using awk. Is this possible??
If so could... (1 Reply)
Hi, I've written the following code to manipulate the first 40 lines of a data file into my desired order:
#!/bin/awk -f
{ if (NR<=(4)){
a=a$0" "}
else { if ((NR >= (5)) && (NR <= (13))) {
b=b$0" " }
else {if ((NR >= (14)) && (NR <= (25))){
c=c$0" "}
... (5 Replies)
Hi,
I have spent the afternoon trawling Google, Unix.com and Unix in a Nutshell for information on how awk arrays work, and I'm not really getting too far.
I ahve a batch of code that I am pretty sure can be better managed using awk, but I'm not sure how to use awk arrays to do what I'm... (1 Reply)
Hi,
I have the following data in a file for example:
Name="Fred","Bob","Peterson","Susan","Weseley"
Age="24","30","28","23","45"
Study="English","Engineering","Physics","Maths","Psychology"
Code="0","0","1","1","0"
Name="Fred2","Bob2","Peterson2","Susan2","Weseley2"... (14 Replies)
Hi
Can someone please explain the logic of awk arrays. I have been doing some reading but I dont understand this:
#!/usr/bin/gawk -f
{
arr++;
}
end
{
for(i in arr)
{
print arr,i
}
}
As I understand arr refs the arrays index, so while $2 is a string that cant... (2 Replies)
Hi, buddies
I am new to shell scripting and trying to solve a problem. I read about arrays in awk that they are quite powerful and are associative in nature.
Awk Gurus Please help!
I have a file:
Id1 pp1 0t4 pp8 xy2
Id43 009y black
Id6 red xy2
Id12 new pp1 black
I have... (5 Replies)
I'm a little stuck and would be grateful of some advice!
I have three files, two of which contain reference data that I want to add to a line of output in the third file. I can't seem to get awk to print array contents as I would expect.
The input files are:
# Input file
AAA,OAA,0313... (2 Replies)
Discussion started by: maccas17
2 Replies
LEARN ABOUT CENTOS
shell-quote
SHELL-QUOTE(1) User Contributed Perl Documentation SHELL-QUOTE(1)NAME
shell-quote - quote arguments for safe use, unmodified in a shell command
SYNOPSIS
shell-quote [switch]... arg...
DESCRIPTION
shell-quote lets you pass arbitrary strings through the shell so that they won't be changed by the shell. This lets you process commands
or files with embedded white space or shell globbing characters safely. Here are a few examples.
EXAMPLES
ssh preserving args
When running a remote command with ssh, ssh doesn't preserve the separate arguments it receives. It just joins them with spaces and
passes them to "$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 v5.16.3 2010-06-11 SHELL-QUOTE(1)