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1

I'm trying to create a new variable using the value of an existing variable as part of the variable name.

filemsg"$word1"=" "

I've also tried 

filemsg$word1=" "

filemsg${word1}=" "

on all attempts I get the following when that line executes,

cicserrors.sh[45]: filemsgCICS= : not found [No such file or directory]
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3  
You may want to use hashes/associative arrays instead (or perl or other real programming language) –  Stéphane Chazelas Nov 1 '13 at 13:18

2 Answers 2

up vote 5 down vote

Use eval:

filemsgCICS=foo
word1=CICS
eval "echo \"\$filemsg$word1\"" # => foo
eval "filemsg$word1=bar"
echo "$filemsgCICS" # => bar

but think twice if you really need it this way.

Another way in ksh93 is to use namerefs:

word1=CICS
nameref v=filemsg$word1
v="xxx" 
echo "$filemsgCICS" # => xxx

For even more nasty hacks like that look here.

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Thanks. That got it working nicely. –  dazedandconfused Nov 1 '13 at 13:37
1  
@dazedandconfused: Naming variables on the fly is the sort of thing that will have programmers and code maintainers waiting for you in a dark alley for the purposes of beating you with surplus power cords. It's really not a best practice. –  Satanicpuppy Nov 1 '13 at 14:10
    
I agree with @Satanicpuppy: it is a practice to discourage, in my opinion. –  MariusMatutiae Nov 1 '13 at 16:11
up vote 0 down vote

export does this far more safely than does eval because there is no danger of it executing shell code following a shell token. But it does export the variables so you can take it as you will.

export "filemsg$word1= "
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