command line options
Chip Salzenberg
chip at ateng.UUCP
Mon Apr 11 23:41:41 AEST 1988
What's so hard about typing '-\?' to get help? I do it all the time.
And it works in any shell and despite strangely named files.
BTW, the argument against '-?' that goes "but what if I have a file named
'-r'" is not very strong, since such a file kills you even if you don't
ask for help:
% ls -F
-r
foo
bar
important/
% rm * [pronounced "rim splat", by the way]
% ls
% [anguished scream]
Kaboom.
For those of you who want to make your programs a bit safer to use than rm,
here is an idea: Before parsing for options, check to see if any arguments
that begin with '-' are actually the names of existing files. If they are,
emit a suitably alarming warning message and enable the "interactive"
option so the user has a chance to back out.
And if you see an argument '--', check to see if a file by that name exists,
then stop looping since the rest of the arguments are not options.
Of course, this gets complicated by a call to isatty(), since you don't
want a cron task waiting for operator input; so perhaps this ends up being
more of a kludge than a safety belt. But if your program is sufficiently
destructive, CYA is a worthwhile policy.
--
Chip Salzenberg "chip at ateng.UU.NET" or "codas!ateng!chip"
A T Engineering My employer's opinions are a trade secret.
"Anything that works is better than anything that doesn't."
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