First of all, you must put in 'ticks' not "quotes" around the embedded g/awk code, because in the latter $1 $2 ... are substituted with positional shell parameters. The shell does this before it passes the code string to g/awk.
I get the following message if I use single quotes:
It runs ok using double quotes
Quote:
Unfortunately your min works only if the first line in output.txt has non-null value, so with your sample data the rest of the algorithm (which I don't really understand) doesn't work out, always printing the input line followed by a zero.
You right! Let me work a bit more on that. Any suggestions to improve the first script so I dont keep using | to stitch it all together?
I need to do a substitution: CPF to ,C,P,F, CPM to ,C,P,M, SPF to ,S,P,F etc. I can do each of them with separate substitutions e.g. s/CPF/,C,P,F/ but I'd like to know if there is a more elegant solution. In general, how can I use the results of the search in the substitution, ... (3 Replies)
Is there a way to simplify stating 1 through to 10, for example in a for loop construct?
for x in 1 2 3 4 5 6 7 8 9 10
do
....
done
I have tried (1-10) with no luck.. thanks (2 Replies)
tcpdump -nr testdump|awk '!/:/;gsub(/^+|+$/,""){print $3};a!~$0;{a=$0};{print $3};!/length/;/./;!/11\:/;!/8 7 6 5 4 3 2 1/;!/UDP/{b=$0} END {for (j=i-1; j>=0; ) print b };{for (i=NF; i>0; i--) printf("%s ",i);printf ("\n")}'
*NOTE IN j>=0 the ; ) was given a space since a smiley is showing up...... (1 Reply)
my script:
FILE="$1"
echo "You Entered $FILE"
if ; then
tmp=$(cat $FILE | sed '/./!d' | sed -n '/regex/,/regex/{/regex/d;p}'| sed -n '/---/,+2!p' | sed -n '/#/!p' | sed 's/^*//' | sed -e\
s/*:// | sed -n '/==> /!p' | sed -n '/--> /!p' | sed -n '/regex/,+1!p' | sed -n '/======/!p' | sed -n... (1 Reply)
Hi,
Is there a way to simplify the below script? Because I am having problems executing this if I added this to CRON. Also, you may notice that its objective is to put all information in one file (rm1.txt). And in addition file "sRMR_6.txt" to sRMR_23.txt" changes its information everyday.... (4 Replies)
Hello,
I have a large number of sed commands that I execute one after the other, simply because I don't know if there's a shorter way to do it. I hope someone can help me save some time :-)
These are my commands:
1.) remove all " in the file:
sed -e 's/\"//g' file
2.) insert ( and... (3 Replies)
the code below is a small fragment of the actual line, in fact i have about 20 values i'm comparing and want to know if it can be simplified. other than the x.xx.xx format of the value they have nothing in common
if || || ; then
do this
else
do this
fiany suggestions? (6 Replies)
Hi all, I don't have much experience with shell scripting and I was wondering if there's a shorter way to write this.
Basically, given a list of strings separated by new lines, I want to prepend each string with a prefix and separate the strings with commas
i.e.
stra
strb
strc
becomes... (3 Replies)
Hello,
I want to submit my awk script into cluster queue as my job takes about forty minutes to finish so I can not run it on the main node.
My awk script is like the following and I have three files. so, I write :
qsub -q short.q Myscript.awk file1 file2 file3
It submits the work into... (1 Reply)
I have the following script:
awk -F "," '{ if ( $4 > 450 && $4 < 550 && $5 > 0.5 ) print $2, $5; else print $2, "0" }' test.txt | awk '{a+=$2}END{for(i in a){print i, a}}' | sort -nk 1.2 | sed 1,2d
and a bunch of files that look like the test file attached here.
I am outputting all... (2 Replies)
Discussion started by: Xterra
2 Replies
LEARN ABOUT CENTOS
shell-quote
SHELL-QUOTE(1) User Contributed Perl Documentation SHELL-QUOTE(1)NAME
shell-quote - quote arguments for safe use, unmodified in a shell command
SYNOPSIS
shell-quote [switch]... arg...
DESCRIPTION
shell-quote lets you pass arbitrary strings through the shell so that they won't be changed by the shell. This lets you process commands
or files with embedded white space or shell globbing characters safely. Here are a few examples.
EXAMPLES
ssh preserving args
When running a remote command with ssh, ssh doesn't preserve the separate arguments it receives. It just joins them with spaces and
passes them to "$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)