Add a new command in bash

[nbanbc]

Hi everyone,

I 'm writing a script these days and I need to use the command: string

link=*ttp://linux.about.com/library/cmd/blcmdln_string.htm ( I am a newbie so the forum doesn't allow to post URLs yet )


The bash, however, answers: command not found...
I tried: "yum install string", but it didn't work.

Any suggestions?

[drl]

Hi.

Yes, the link does make string seem like a useful command. However, if you look carefully, you will notice references to tcl in places.

This identifies it as a tcl command. It is not a command available directly through a shell like bash. The page does not do a good job of making that clear.

Look at the man pages for bash or expr for some string manipulation features.

Below is an example of string being used in a tclsh script with an example from the link you posted.

Best wishes ... cheers, drl

#!/usr/bin/env tclsh

# @(#) tcl2     Demonstrate tclsh feature: "string" command.

set version [ info tclversion ]
set message " Hello, world from tclsh ($version)"
puts stdout $message

puts stdout ""
set v1 [ string first a 0a23456789abcdef 5 ]
puts stdout [ join [ list " variable v1 is " $v1 ] ]

exit 0

producing:

% ./tcl2
 Hello, world from tclsh (8.4)

 variable v1 is  10

[nbanbc]

Found it!!!

I needed

string range $mystring 3 end

where mystring="###123", in order to put 123 in a variable...

But,

len=`expr length $mystring`
var=`expr substr $line 4 $len`

works fine in bash.

Thanks for your help.