This question is a sequel of sorts to my earlier question. The users on this site kindly helped me determine how to write a bash for loop that iterates over string values. For example, suppose that a loop control variable fname iterates over the strings "a.txt" "b.txt" "c.txt". I would like to echo "yes!" when fname has the value "a.txt" or "c.txt", and echo "no!" otherwise. I have tried the following bash shell script:
#!/bin/bash
for fname in "a.txt" "b.txt" "c.txt"
do
echo $fname
if [ "$fname" = "a.txt" ] | [ "$fname" = "c.txt" ]; then
echo "yes!"
else
echo "no!"
fi
done
I obtain the output:
a.txt
no!
b.txt
no!
c.txt
yes!
Why does the if statement apparently yield true when fname has the value "a.txt"? Have I used | incorrectly?