Combining Tests || &&

Combining Tests
It is possible to combine tests by using the && and || operators. These perform a Logical AND and
Logical OR, respectively.

#!/bin/bash
filename=${1:-/etc/hosts}
if [ -r “$filename” ] && [ -s “$filename” ]; then
md5sum $filename
else
echo “$filename can not be processed”
fi
# Show the file if possible
ls -ld $filename 2>/dev/null
-----------
cat f
filename=$1
[ -r $filename ] || echo “$filename is not readable”

bash f /etc/shadow

“/etc/shadow is not readable”

ubuntu2@ubuntu2:~/Documents/shellscripting$ bash f t/

cat f

filename=$1

[ -r $filename ] && echo “$filename is readable”

bash f t/

“t/ is readable”

ubuntu2@ubuntu2:~/Documents/shellscripting$ bash f /etc/shadow

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