Timeline for Is it true that "do ... done" blocks in Bash do not end with "od" because od existed before Bash/Bourne shell?
Current License: CC BY-SA 4.0
19 events
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| Jun 24, 2021 at 18:08 | comment | added | Charles Duffy | @DungSaga, ... remember, original Bourne is a product of the 1970s, whereas POSIX sh was standardized in 1992 (at which time ksh -- from which both bash and the POSIX sh spec drew inspiration -- had substantially improved the state of the art). That's a lot of years for nothing to change; of course a new shell released at the end of the 80s would be more similar to its contemporaries than to something a decade older. | |
| Jun 24, 2021 at 18:01 | comment | added | Charles Duffy |
@DungSaga, try echo hello ^ cat. In POSIX sh or bash it outputs hello ^ cat; in real original Bourne it outputs just hello. (That test is how GNU autoconf distinguishes between original Bourne and POSIX-family shells like ash, dash, or bash).
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| Jun 24, 2021 at 17:49 | comment | added | DungSaga |
@toby-speight Maybe he started to feel the awkwardness of typing a long word in reverse. A short word is easier to recognize, even when it's written backward. That could be the reason why he used CASE/ESAC instead of SWITCH/HCTIWS.
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| Jun 24, 2021 at 17:20 | comment | added | DungSaga | @charles-duffy I heard that Bash was designed to be a free software replacement for Bourne shell. and Bash syntax is a superset of Bourne shell syntax. That's why I think Bash is compatible with Bourne shell. But I may be wrong :D PS: Charles Duffy, your avatar is so cool. it's symmetric calligraphy. | |
| Jun 23, 2021 at 17:42 | comment | added | Charles Duffy |
@DungSaga, ...it's a bit more indirect than that. bash isn't compatible with Bourne -- rather, it's compatible with POSIX sh. The POSIX sh standard definitely has a huge amount of Bourne influence, but compatible they're not -- for example, in true Bourne shell, ^ is a secondary pipe character, whereas it doesn't work that way in either POSIX sh or bash. There's an argument to be made that the POSIX sh standard was more closely drawn from ksh, which was modeled off Bourne...
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| Jun 23, 2021 at 16:36 | comment | added | Toby Speight |
ENDSW instead of HCTIWS - what was SRB thinking??!
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| Jun 23, 2021 at 14:07 | comment | added | chepner |
A more direct suggestion that the program od prevented the use of od as a keyword can be found (sans citation) in en.wikipedia.org/wiki/Od_(Unix).
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| Jun 23, 2021 at 9:42 | comment | added | DungSaga | @user3840170 I guess because this page saves time and prevent the risk of getting lost while wandering to the Wikipedia forest ;D BTW I like the thoughts you put in your user description, such as: The best questions are atomic, focused on a single problem. The worst questions are those that require untangling several layers of confusion. | |
| Jun 23, 2021 at 9:31 | comment | added | DungSaga |
@texdr.aft Great! What are these #define used for?
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| Jun 23, 2021 at 9:31 | comment | added | user3840170 | @DungSaga Why would someone come to ask questions or read answers here if it’s just quotes from Wikipedia? I’d just go to Wikipedia. | |
| Jun 23, 2021 at 9:10 | comment | added | texdr.aft |
Bourne's pseudo-Algol C code used od: tuhs.org/cgi-bin/utree.pl?file=V7/usr/src/cmd/sh/mac.h
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| S Jun 23, 2021 at 8:56 | history | suggested | DungSaga | CC BY-SA 4.0 |
add a quote from wikipedia
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| Jun 23, 2021 at 8:53 | comment | added | DungSaga | thanks for your answer. I hope you don't mind when I edited it to add a quote from wikipedia. | |
| Jun 23, 2021 at 8:51 | review | Suggested edits | |||
| S Jun 23, 2021 at 8:56 | |||||
| Jun 23, 2021 at 8:45 | vote | accept | DungSaga | ||
| Jun 23, 2021 at 8:05 | comment | added | texdr.aft | @DungSaga You're right. | |
| Jun 23, 2021 at 8:05 | history | edited | texdr.aft | CC BY-SA 4.0 |
precision
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| Jun 23, 2021 at 8:01 | comment | added | DungSaga | Bash was designed to be compatible with Bourne shell. And Bourne shell ripped the control structures from Algol 68 | |
| Jun 23, 2021 at 6:08 | history | answered | texdr.aft | CC BY-SA 4.0 |