Hi there,
I want some help on scripting regarding file processing.
I have a scenario in which I have 10 files. (file1.txt, file2.txt....) and they are in paricular format.
I want to read these files and append some text lines at the begining of each file and write this updated contents of... (2 Replies)
Hi All,
Query 1 :
I want to know how we can get a count of multipe occurrences of a particular expression in another string.
For Eg. If my string is " 12" and i need to count the number of spaces preceeding 12
Query 2 :
Also want to know how we can change the alignment of a... (9 Replies)
Hi
I have a tab delimited file with 3 fields. I need to sort this file on the first field and remove all the records where the first field has dulplicates. For eg my file is
133|arrfdfdg|sdfdsg
234|asfsdgfs|aasdfs
133|affbfsde|dgfg
When this file gets sorted I need the result to be ... (2 Replies)
Hi :)
I am writing a ksh
I have a string of general format
A12B3456CD78
the string is of variable length
the string always ends with numbers (here it is 78.. it can be any number of digits may be 789 or just 7)
before these ending numbers are alphabets (here it is CD can even be... (3 Replies)
Hey everyone. So the background of the problem is that the ps3 does not support the mkv container, but DOES support the avi one. Here is the script to convert one file with the name hardcoded in:
#!/bin/sh
mencoder -oac... (2 Replies)
Hi All,
can you tell me how to drop all preceding zeros in a number. For example, if i have a numbers like 000876838347 and 0000007854762543..how to make them as 876838347 and 7854762543. (6 Replies)
Hi everyone,
I need little help in shell operations from C++ program.
Here I furnish the details of problem:
1. Lets say my current working path is myWorkingPath.
2. In my working path I have list of name directories and each name directory has two more sub directories say A/B.
(now path to... (5 Replies)
Hi Folks,
Below is example of an Input data which is used, based on the last 2, 3 & 4 column, I want my first column data to be collated as shown in the output section.
a,ac,tc,ic
b,ac,tc,ic
c,ac,tc,ic
d,ac,tc,ic
b,bc,tc,ic
d,bc,tc,ic
e,bc,tc,ic
I want my output to be
... (2 Replies)
Discussion started by: nikhil jain
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)