As my home work, I tried to figure it out how it works (though I know it works) but still no luck:-( Would someone elabrate a little of the syntax for me? Many thanks in advance!
Hi there
I have a file with a variable amount of rows but the 45th, 46th and 47th charachter of each line is the status field which is a three digit code ie 001, 002, 003 etc. My question is this..I need to strip all the records/lines with 002's out of the file completely and put them into... (14 Replies)
Can anyone tell me what could be the solution to following :
I have one .txt file which contains some "seed" information. This seed may appear multiple time in the file so what I want do is if this seed appears again in the file then that line should be removed.
Please provide the script code... (4 Replies)
Hello,
I've to change the shell in /etc/passwd for some users .
I've the list of users but I'm not able to modify the file with scripting .
I'm working on a Sol10 .
Can anyone help me ?
tnks (7 Replies)
I have searched the forum for this - forgive me if I missed a previous post.
I have the following file:
blah blah blah
blah blah blah
blah blah blah
blah blah blah
blah blah blah
alter table "informix".esc_acct add constraint (foreign key (fi_id)
references "informix".fi ... (5 Replies)
Hi,
I have requirement that I need to split my input file into two files based on a search pattern "abc"
For eg. my input file has below content
abc
defgh
zyx
I need file 1 with
abc
and file2 with
defgh
zyx
I can use grep command to acheive this. But with grep I need... (8 Replies)
I am trying to remove lines in the target.txt file if $5 before the - in that file matches sorted_list. I have tried grep and awk. Thank you :).
grep
grep -v -F -f targets.bed sort_list
grep -vFf sort_list targets
awk
awk -F, '
> FILENAME == ARGV {to_remove=1; next}
> ! ($5 in... (2 Replies)
In the awk piped to sed below I am trying to format file by removing the odd xxxx_digits and whitespace after, then move the even xxxx_digit to the line above it and add a space between them. There may be multiple lines in file but they are in the same format. The Filename_ID line is the last line... (4 Replies)
Discussion started by: cmccabe
4 Replies
LEARN ABOUT CENTOS
shell-quote
SHELL-QUOTE(1) User Contributed Perl Documentation SHELL-QUOTE(1)NAME
shell-quote - quote arguments for safe use, unmodified in a shell command
SYNOPSIS
shell-quote [switch]... arg...
DESCRIPTION
shell-quote lets you pass arbitrary strings through the shell so that they won't be changed by the shell. This lets you process commands
or files with embedded white space or shell globbing characters safely. Here are a few examples.
EXAMPLES
ssh preserving args
When running a remote command with ssh, ssh doesn't preserve the separate arguments it receives. It just joins them with spaces and
passes them to "$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)