hpr2756 :: Bash Tips - 20
Deleting arrays; positional and special parameters in Bash
Hosted by Dave Morriss on Monday, 2019-02-25 is flagged as Explicit and is released under a CC-BY-SA license.
Bash, array, delete, positional parameters.
1.
The show is available on the Internet Archive at: https://archive.org/details/hpr2756
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Duration: 00:32:35
Bash Scripting.
This is an open series in which Hacker Public Radio Listeners can share their Bash scripting knowledge and experience with the community. General programming topics and Bash commands are explored along with some tutorials for the complete novice.
Tidying loose ends (Some collateral Bash tips)
Deleting arrays
I forgot to cover one thing on my list when doing the last show: I forgot to explain how to delete arrays and array elements. I’ll cover that topic in this episode.
Positional and Special parameters
I have also avoided talking much about the positional and special parameters in Bash: '$1', '$2', '$#' and the rest. I will cover (some of) these in this episode.
Silly titles
I stopped doing the weird episode titles by episode 14 because I thought the joke was getting tired. However, I think a few people missed them (and a certain HPR colleague was found vandalising my new titles as they were being posted ;-), so I have added them inside the notes on the older shows and am adding one here – as a homage to silliness.
Long notes
I have provided detailed notes as usual for this episode, and these can be viewed here.
Links
- “GNU BASH Reference Manual”
- Section “3.4 Shell Parameters”
- Section “4 Shell Builtin Commands”
- Section “4.1 Bourne Shell Builtins”
- Section “4.2 Bash Builtin Commands”
- Section “4.3.1 The Set Builtin”
POSIX Shell Command Language: unset
- Previous episodes under the heading Bash Tips:
- HPR episode 1648 “Bash parameter manipulation”
- HPR episode 1843 “Some Bash tips”
- HPR episode 1884 “Some more Bash tips”
- HPR episode 1903 “Some further Bash tips”
- HPR episode 1951 “Some additional Bash tips”
- HPR episode 2045 “Some other Bash tips”
- HPR episode 2278 “Some supplementary Bash tips”
- HPR episode 2293 “More supplementary Bash tips”
- HPR episode 2639 “Some ancillary Bash tips - 9”
- HPR episode 2649 “More ancillary Bash tips - 10”
- HPR episode 2659 “Further ancillary Bash tips - 11”
- HPR episode 2669 “Additional ancillary Bash tips - 12”
- HPR episode 2679 “Extra ancillary Bash tips - 13”
- HPR episode 2689 “Bash Tips - 14 (Some auxiliary Bash tips)”
- HPR episode 2699 “Bash Tips - 15 (More auxiliary Bash tips)”
- HPR episode 2709 “Bash Tips - 16 (Further auxiliary Bash tips)”
- HPR episode 2719 “Bash Tips - 17 (Additional auxiliary Bash tips)”
- HPR episode 2729 “Bash Tips - 18 (Extra auxiliary Bash tips)”
- HPR episode 2739 “Bash Tips - 19 (Supplemental auxiliary Bash tips)”
- Resources:
- Examples: bash20_ex1.sh, bash20_ex2.sh