Special Variables ($0 $1 $?)
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Special Variables ($0 $1 $?)
$0 is the script's own name, $1, $2, etc. are positional arguments passed to the script, and $? holds the exit status of the most recently run command. $# gives the number of arguments, and $@ expands to all of them. These special variables are essential for writing scripts that accept input and check for errors.
Note: Always check $? right after the command you care about — it gets overwritten by every subsequent command.
Example: Special Variables ($0 $1 $?)
#!/bin/bash
echo "Script name: $0"
echo "First arg: $1"
echo "Arg count: $#"
true
echo "Exit status of true: $?"
false
echo "Exit status of false: $?"Login to try C/C++/Java/PHP code in the editor
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