Shell Programming and Scripting

You could do this...
cat felix.whoals | awk '
{
cmd=sprintf("ps -au %s",$1);
print cmd
system (cmd);
}'

So this cannot be solved without awk and sed? I do not want to use these two commands because I want to use the long way to do it. Do you have another solution without using awk?

Programs are run by specifying a name and some optional arguments and additionally some IO redirection.

In the first case you refer to program called "head" with arguments "-1" and "abc".

In the second case you refer to a program called "ps" with arguments "-au", "head", "-1" and "abc".

Do you mean

Code:

ps -au `head -1 abc`

so that the output of "head -1 abc" becomes a command line argument?

Code:

ps -au `cat filename`

There might be 1000 good ways to do this, but you probably won't find one any better, shorter, or less complicated. The example can be done in one line, just takeout the newlines and the print statement. If you want to print the cmd, the statement probably needs to look like: print(cmd); (notice the parens and semi colon).

yes.

ps -au `head -1 abc` where head -1 abc gives me an argument (username) and then I could use it to get the process running for the current username.

Do you know the way to fix it?

um,

Code:

echo $LOGNAME

will give the current user

Code:

ps -au `echo $LOGNAME`

would do want you want but can be simplified to

Code:

ps -au $LOGNAME