Shell Programming and Scripting

I create commands within a pipe and finally want them to be executed instead of being displayed on the screen. What is the last stage in this pipe? I found by guessing that "ksh" is working, but is this the best to use here?

It boils down to this:

Code:

 echo "print Hello World!"| ksh

What is the "best" command at the end of the pipe to execute the commands that come down the pipe?

Try this instead of pipe

Code:

echo 'print Hello World' >/dev/null  2>&1

meaning redirect both output and errors to /dev/null

??? ... that's not what I asked for. Was I that unclear?

Hello Akshay Hegde/Cochise,

There is no meaning for using >/dev/null 2>&1 in case of echo. We can use this command if we are running any script and we want to see output if that script is storing it in any output file, also it will avoid errors too while execution of script too. There this command can be useful.

./script.ksh >/dev/null 2>&1


Thanks,
R. Singh

I am sorry, what kind of commands you are creating ? its bit unclear to me, whether you are trying to create commands which can be executed on shell ? is so you are on right path you can ksh, sh etc.

ksh is "best" if you want to use ksh.
sh is "best" if you want to use sh.
zsh is "best" if you want to use zsh.

etc.

But why bother? Why not just run the command, instead of printing it? Shell-within-shell or eval bruteforcing usually means something else was forgotten along the way.

For better understanding of my problem, here is the long story:

I have a large log file, that has some lines like this:

Code:

skipping: /usr/bin/chuser "gecos=ipsec;MDE0M819;;F" ipsec (TESTMODE)
skipping: /usr/bin/chuser "gecos=nobody;MDE0M819;;F" nobody (TESTMODE)
skipping: /usr/bin/chuser "gecos=perfmgr;MDE0M819;;F" perfmgr (TESTMODE)

The lines may occur multiple times.

I want to find these lines, remove duplicates, strip off "skipping:" and "(TESTMODE)" and then execute the remainining chuser command.

What I have built is this:

Code:

grep 'chuser "gecos=' modify.LOG|sort|uniq|sed 's/skipping: //; s/ (TESTMODE)//'|ksh

This works and is what I asked for.

New question: I would like to have the command string displayed on the terminal before it is send to ksh for execution.
Is there a smarter and shorter way than doing it in a do loop like below?

Code:

grep 'chuser "gecos=' modify.LOG|sort|uniq|sed 's/skipping: //; s/ (TESTMODE)//'|while read line;do print - $line;ksh "$line";done