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Newbie bash scripting help requested

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# 8  
Old 05-10-2010
Quote:
Originally Posted by scottn
(to your first statement, change "or does it mean" to "and does it mean", and the answer would be "yes" to both)
Smilie

How can a non-empty variable evaluate to 'true' _and_ a variable containing, say, the value '1' evaluate to 'false'?
# 9  
Old 05-10-2010
Quote:
Originally Posted by Carson Dyle
Smilie

How can a non-empty variable evaluate to 'true' _and_ a variable containing, say, the value '1' evaluate to 'false'?
You're maybe confusing return codes with variables / strings that functions echo or print. The two have nothing to do with each other.

Code:
$ cat some_script
function some_func {
  echo 1
  return 0
}

if some_func; then
  echo TRUE
else
  echo FALSE
fi

some_func


$ ./some_script
1
TRUE

Code:
$ cat some_script
function some_func {
  echo 1
  return 1
}

if some_func; then
  echo TRUE
else
  echo FALSE
fi

some_func


$ ./some_script
1
FALSE

Last edited by Scott; 05-10-2010 at 10:01 AM..
# 10  
Old 05-10-2010
Thanks. I think I've got it now.
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