11-15-2011
Differences in printed commands after execution with same code
I have a korn shell script that executes a function which is stored in a common library. In the function there is obviously some code. Here is the line of code in the function in question:
temp=`echo $status_cnt|tr -d [0-9]`
When the shell script executes with set -x, I'm seeing that on most occasions that the below commands and their arguments are printed as expected based on the above line of code. I'll call this the desired result.
Desired Result
+ + echo 2
+ tr -d [0-9]
However on other, less frequent occasions, I'm seeing the below commands and arguments when the code is executed. I'll call this the undesired result.
Undesired Results
+ + tr -d 2
+ echo 2
Assuming the code in the function is identical on all occasions, what would cause the deviation between the desired and undesired results?
Firstly, why would the 2 commands appear in different order (i.e. shouldn't I always expect the echo to be printed first in the desired result since the echo command precedes the tr -d [0-9] command when being assigned to temp variable)?
Secondly, what would cause the tr -d [0-9] to be printed as tr -d 2?
Thanks in advance!
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