Editing Bash (Unix shell) (section)

==== Settings and Shell Options ====
===== The <code>set</code> Built-in =====
* Xtrace: [ <code>set -x</code> | <code>set -o xtrace</code> ]
The shell's primary means of debugging. Both xtrace and verbose can be turned off at the same time with the command <code>set -</code>.
* Verbose: [ <code>set -v</code> | <code>set -o verbose</code> ]
Prints a command to the terminal as Bash reads it. Bash reads constructs all at once, such as compound commands which include if-fi and case-esac blocks. If a <code>set -v</code> is included within a compound command, then "verbose" will be enabled the next time Bash reads code as input, i.e., after the end of the currently executing construct.<ref>{{Cite mailing list |mailing-list=bug-bash |date=20 April 2021     |title=bug-bash archives, Re: Document that set -v inside case statements is special     |url=https://lists.gnu.org/archive/html/bug-bash/2021-04/msg00172.html  }}</ref> Both xtrace and verbose can be turned off at the same time with the command <code>set -</code>.

===== The <code>shopt</code> Built-in =====
* expand-aliases
On by default in interactive shells. Some developers discourage its use in scripts.

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=== Reporting the Time ===
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'''+++ The <code>printf</code> Builtin (and not the Binary)'''

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