A shebang or hashbang is a particular line that often begins
scripts. The line begins with the characters
#!. This line defines
which program should be passed the contents of the file. For
#!/bin/sh echo "Hi there!"
The paths in the shebang line may be different of different
env program exists to solve this problem and make
scripts portable. This program looks in the user's
$PATH to find
the location of an application. The path
/user/bin/env is commonly
used for this utility.
#!/usr/bin/env sh echo "Hi there!"
Once a shebang line exists, the
chmod command can be used to make
a script executable.
chmod +x script.sh ./script.sh
The first line adds (
+) the executable (
x) permission to the