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Using let in bash

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Top Forums Shell Programming and Scripting Using let in bash
# 1  
Old 03-24-2011
Using let in bash
Hello,

I am new to shell scripting. I am trying to learn it by reading a manual and practice on a box. I was trying to see how the let command would give me some results. I built this little script, but I always got an error stating , let: not found. Can you please help?
Code:
#!/bin/bash
a=5
b=7
c=0
let "c=$a+$b"
echo "c = $c"
exit 0

Moderator's Comments:
Mod Comment Please use [code] and [/code] tags when posting code, data or logs etc. to preserve formatting and enhance readability, thanks.


Thanks for your help,
Last edited by Pouchie1; 03-24-2011 at 12:50 PM.. Reason: code tags
# 2  
Old 03-24-2011
You must have a very old version of BASH. What does bash --version print?

All versions of BASH ought to support the eval syntax, though, or the KSH syntax:

Code:
((A=5+4))
echo $A

# 3  
Old 03-24-2011
The version is 3.2.39 . I guess the let utility is not installed. Man let does not return anything. Thanks,
# 4  
Old 03-24-2011
Quote:
Originally Posted by Pouchie1
The version is 3.2.39
But what did it actually print? It might have been dash or something, not bash.
Quote:
I guess the let utility is not installed.
It's not a utility, it's part of the shell, and really couldn't ever be anything but part of the shell since it modifies shell variables.
# 5  
Old 04-03-2011
I got it to work. Thank you!
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