Is there any tool in which I can place the script and it can tell me the meaning of the whole script?
Yes, there is: it is called "scripting learning device", or, by its old name, "book". I suggest you get one and start reading.
Make sure that you are learning the right shell, though. In the first line of the script there should be a "shebang" identifying the shell to use, for example:
Widespread alternatives to this would be "ksh" (Korn Shell) or "sh" (either Bourne shell or the systems default shell, whatever that may be).
Most of the syntax is the same in these shells (they are all derived from the Bourne shell) but in some details they are different.
Hello all,
Could any one let me know where to find exercises(problems to solve) both simple and complex ones that would eventually help me learn Shell scripting.I'm just a beginner:o in shell scripting but would love to learn more..
Thanks,
Triji (2 Replies)
I am trying to write a small (and rather simple) script to gather some info about the system and piping it to dzen2
first, i want to explain some things.
I know i could have used conky, but my intention was to expand my knowledge of bash, pipes and redirections inside a script, and to have fun... (14 Replies)
Hi folks,
I'm a CS students enrolled in a sysadmin class where we've been covering bash scripting for the past few weeks. I have prior knowledge in java, c++, c#, python,and some scripting languages like asp.net w/c# and php. This bash stuff seems pretty neat and a bit different than what I am... (9 Replies)
I am beginner to the SHELL SCRIPT and want to Learn SHELL SCRIPT Basics.
This thread should help to all beginners who want to learn SHELL SCRIPT
*** Thanks in advance to those who will contribute on this thread ***
Please guide me and all beginners...
1. Is there any good e-book... (3 Replies)
I'm going to be starting a job in a month or so that I need to brush up on my Unix shell scripting skills. About 15 years ago, I took a college class for Unix shell scripting. I would like to find a good college book again, rather than just going to Amazon and just buying anything.
This is... (2 Replies)
Hi Guys,
I know basic command of unix and basic programming of unix as like using for loop, while loop, if..else, case statement etc. then how to learn unix shell scripting as well as use also. (1 Reply)
Discussion started by: aaditya321
1 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)