LFS201 LAB 37.3

Brucecurcio

Can someone tell me what the "set -x" syntax at the beginning of the script on item 6 in this lab means?

#!/bin/bash

set -x

rsync --progress -zvrxH -e "ssh -c blowfish" --delete $*

I looked under the set man page, which explains that it identifies a key sequence that executes a shell command. I'm not really sure what this means or how it is used here.

coop

It means turn on debugging, which means echoing all commands
to the console *before* they are executed, essentially it means verbose.
You turn off this debug mode with set +x. This is all buried somewhere in the man
page for bash, not set. It is also discussed in the "debugging" section of the
bash chapter I'm pretty sure, but I don't have the class in front of me.

so you often do:

set -x

... some commands

set +x

when you want to get more detailed output, often but not exclusively, while debugging
a script.