Bash Getting started with Bash Hello World in "Debug" mode
Example
$ cat hello.sh
#!/bin/bash
echo "Hello World"
$ bash -x hello.sh
+ echo Hello World
Hello World
The -x argument enables you to walk through each line in the script. One good example is here:
$ cat hello.sh
#!/bin/bash
echo "Hello World\n"
adding_string_to_number="s"
v=$(expr 5 + $adding_string_to_number)
$ ./hello.sh
Hello World
expr: non-integer argument
The above prompted error is not enough to trace the script; however, using the following way gives you a better sense where to look for the error in the script.
$ bash -x hello.sh
+ echo Hello World\n
Hello World
+ adding_string_to_number=s
+ expr 5 + s
expr: non-integer argument
+ v=
