[TUHS] Re: Of flags and keyletters

[TUHS] Re: Of flags and keyletters

[Noel Chiappa]

    > From: Bakul Shah

    > Use of "flag" for this purpose seems strange. "option" makes more sense.

People on this list seem to forget that there were computers before UNIX.

The _syntax_ of "-f" probably predates any UNIX; Multics used it extensively.
See the "Introduction to Multics", MAC-TR-123, January 1974 (a little after
UNIX V1, but I expect I could probably track it back further in time, if I
cared to put in the effort); pg. 3-24.

Interestingly, I looked though the CTSS manual, and CTSS did not seem to use
this syntax for flag arguments: see, e.g., the SAVE command (section AH.3.03).


The _name_ "flag" came in early on UNIX. (Multics called them "arguments";
see above, pg. 3-27, top line.) We can see this happen - see:

  http://squoze.net/UNIX/v1man/man1/du

which calls the "-a" and "-s" "arguments"; but in:

  http://squoze.net/UNIX/v1man/man1/ld

"-s", "-u", etc are called "flag arguments".

Long enough ago that certainty about the etymology/rationale is probably now
lost.

	Noel

[TUHS] Re: Of flags and keyletters

[Aaron]

Having written the first versions of getopt(3), getopt(1), and associated man pages around 1979, I do not recall any real orthodoxy in the use of ‘options’ vs ‘flags.’ In general, ‘flags’ seemed to be reserved for single arguments in the form of ‘-x’

I wrote getopt, and rewrote many commands to use it because I got annoyed at trying to remember which commands required “-x -y -z” vs “-xyz”, and which flags required or allowed optional  arguments.

Aaron 



> On Mar 2, 2024, at 5:22 PM, jnc@mercury.lcs.mit.edu wrote:
> 
> 
>> 
>> From: Bakul Shah
> 
>> Use of "flag" for this purpose seems strange. "option" makes more sense.
> 
> People on this list seem to forget that there were computers before UNIX.
> 
> The _syntax_ of "-f" probably predates any UNIX; Multics used it extensively.
> See the "Introduction to Multics", MAC-TR-123, January 1974 (a little after
> UNIX V1, but I expect I could probably track it back further in time, if I
> cared to put in the effort); pg. 3-24.
> 
> Interestingly, I looked though the CTSS manual, and CTSS did not seem to use
> this syntax for flag arguments: see, e.g., the SAVE command (section AH.3.03).
> 
> 
> The _name_ "flag" came in early on UNIX. (Multics called them "arguments";
> see above, pg. 3-27, top line.) We can see this happen - see:
> 
>  http://squoze.net/UNIX/v1man/man1/du
> 
> which calls the "-a" and "-s" "arguments"; but in:
> 
>  http://squoze.net/UNIX/v1man/man1/ld
> 
> "-s", "-u", etc are called "flag arguments".
> 
> Long enough ago that certainty about the etymology/rationale is probably now
> lost.
> 
>    Noel

[TUHS] Re: Of flags and keyletters

[Larry McVoy]

I rewrote getopt() for BitKeeper because I wanted long options and 
wanted to allow optional args but also have required args.

On Sun, Mar 03, 2024 at 12:38:20PM -0500, Aaron wrote:
> Having written the first versions of getopt(3), getopt(1), and associated man pages around 1979, I do not recall any real orthodoxy in the use of ???options??? vs ???flags.??? In general, ???flags??? seemed to be reserved for single arguments in the form of ???-x???
> 
> I wrote getopt, and rewrote many commands to use it because I got annoyed at trying to remember which commands required ???-x -y -z??? vs ???-xyz???, and which flags required or allowed optional  arguments.
> 
> Aaron 
> 
> 
> 
> > On Mar 2, 2024, at 5:22???PM, jnc@mercury.lcs.mit.edu wrote:
> > 
> > ???
> >> 
> >> From: Bakul Shah
> > 
> >> Use of "flag" for this purpose seems strange. "option" makes more sense.
> > 
> > People on this list seem to forget that there were computers before UNIX.
> > 
> > The _syntax_ of "-f" probably predates any UNIX; Multics used it extensively.
> > See the "Introduction to Multics", MAC-TR-123, January 1974 (a little after
> > UNIX V1, but I expect I could probably track it back further in time, if I
> > cared to put in the effort); pg. 3-24.
> > 
> > Interestingly, I looked though the CTSS manual, and CTSS did not seem to use
> > this syntax for flag arguments: see, e.g., the SAVE command (section AH.3.03).
> > 
> > 
> > The _name_ "flag" came in early on UNIX. (Multics called them "arguments";
> > see above, pg. 3-27, top line.) We can see this happen - see:
> > 
> >  http://squoze.net/UNIX/v1man/man1/du
> > 
> > which calls the "-a" and "-s" "arguments"; but in:
> > 
> >  http://squoze.net/UNIX/v1man/man1/ld
> > 
> > "-s", "-u", etc are called "flag arguments".
> > 
> > Long enough ago that certainty about the etymology/rationale is probably now
> > lost.
> > 
> >    Noel

-- 
---
Larry McVoy           Retired to fishing          http://www.mcvoy.com/lm/boat

[TUHS] Re: getopt

[Phil Budne]

Aaron wrote:
> Having written the first versions of getopt(3), getopt(1), and associated man pages around 1979
... 
> I wrote getopt, and rewrote many commands to use it because I got
> annoyed at trying to remember which commands required “-x -y -z” vs
> “-xyz”, and which flags required or allowed optional arguments.

For posterity, can you tell us more about where/when/how it happened?
Where were you working, and on what project??

I found an acknowledgement of your work on p9 of the paper that starts at
https://www.tuhs.org/Archive/Documentation/AUUGN/AUUGN-V05.3.pdf#page=27
"Proposed Syntax Standard for UNIX* System Commands":

	Acknowledgments

	We are indebted to Jerry Vogel and Aaron Cohen: after
	evaluating the problem, we arrived at asolution very similar
	to the one they championed five years ago.

References for the above proposal:
 Hemenway, K., & Armitage, H. (1984) Proposed Syntax Standard for UNIX System Commands. In Summer USENIX Conference. El Cerito, CA: Usenix Association. 

 Proposed syntax standard for UNIX system commands
 K Hemenway, H Armitage - UNIX/world, 1984

[TUHS] Re: Of flags and keyletters

[Aaron]

Unix has long benefited from the notion that everything can be improved!

Sent from my iPhone

> On Mar 3, 2024, at 12:53 PM, Larry McVoy <lm@mcvoy.com> wrote:
> 
> I rewrote getopt() for BitKeeper because I wanted long options and
> wanted to allow optional args but also have required args.
> 
>> On Sun, Mar 03, 2024 at 12:38:20PM -0500, Aaron wrote:
>> Having written the first versions of getopt(3), getopt(1), and associated man pages around 1979, I do not recall any real orthodoxy in the use of ???options??? vs ???flags.??? In general, ???flags??? seemed to be reserved for single arguments in the form of ???-x???
>> 
>> I wrote getopt, and rewrote many commands to use it because I got annoyed at trying to remember which commands required ???-x -y -z??? vs ???-xyz???, and which flags required or allowed optional  arguments.
>> 
>> Aaron
>> 
>> 
>> 
>>>> On Mar 2, 2024, at 5:22???PM, jnc@mercury.lcs.mit.edu wrote:
>>> 
>>> ???
>>>> 
>>>> From: Bakul Shah
>>> 
>>>> Use of "flag" for this purpose seems strange. "option" makes more sense.
>>> 
>>> People on this list seem to forget that there were computers before UNIX.
>>> 
>>> The _syntax_ of "-f" probably predates any UNIX; Multics used it extensively.
>>> See the "Introduction to Multics", MAC-TR-123, January 1974 (a little after
>>> UNIX V1, but I expect I could probably track it back further in time, if I
>>> cared to put in the effort); pg. 3-24.
>>> 
>>> Interestingly, I looked though the CTSS manual, and CTSS did not seem to use
>>> this syntax for flag arguments: see, e.g., the SAVE command (section AH.3.03).
>>> 
>>> 
>>> The _name_ "flag" came in early on UNIX. (Multics called them "arguments";
>>> see above, pg. 3-27, top line.) We can see this happen - see:
>>> 
>>> http://squoze.net/UNIX/v1man/man1/du
>>> 
>>> which calls the "-a" and "-s" "arguments"; but in:
>>> 
>>> http://squoze.net/UNIX/v1man/man1/ld
>>> 
>>> "-s", "-u", etc are called "flag arguments".
>>> 
>>> Long enough ago that certainty about the etymology/rationale is probably now
>>> lost.
>>> 
>>>   Noel
> 
> --
> ---
> Larry McVoy           Retired to fishing          http://www.mcvoy.com/lm/boat

[TUHS] Re: Of flags and keyletters

[Rich Salz]

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On Sun, Mar 3, 2024 at 12:38 PM Aaron <aaronscohen@gmail.com> wrote:

> Having written the first versions of getopt(3), getopt(1), and associated
> man pages around 1979 ...
>

I always thought that this was a brilliant piece of engineering.  In less
than 70 lines, it was a clever, but not obtuse, bit of code to handle the
most common option/flag/switch usages that pervaded the Unix ecosystem at
the time.  Thanks for that!

Source: https://www.linux.co.cr/unix-source-code/review/1985/1103.html

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