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An echo question

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# 1  
Old 04-08-2009
An echo question
Why do get 0 when i enter " echo $? "
# 2  
Old 04-08-2009
The variable "?" is the exit code for the previous command. If you perform a grep for something that does not exist in a file the exit code will be "1" if found it will be "0". The command you ran just prior to the "echo $?" must have exited with a success code of "0".
Code:
content of test.txt = "test"

grep Z test.txt
echo $?
1

grep test test.txt
echo $?
0

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