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Re: [command line arguments] more elegant solution ??

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BartC <bc@freeuk.com> writes:
> On 12/12/2016 00:13, Lew Pitcher wrote:
>> On Sunday December 11 2016 19:02, in comp.lang.c, "Lew Pitcher"
>> <lew.pitcher@digitalfreehold.ca> wrote:
[...]
>>> Witness:
> 18:55 $ ls | wc -l
>>>   157
>>>
>>> That's 157 files and directories in the current directory, including the
>>> source code Args.c
>>>
>>>   18:55 $ cat Args.c
>>>   #include <stdio.h>
>>>   #include <stdlib.h>
>>>
>>>   int main(int argc, char *argv[])
>>>   {
>>>     int argnum;
>>>
>>>     printf("argc == %d\n",argc);
>>>     for (argnum = 0; argnum < argc; ++argnum)
>>>       printf("argv[%d] -> \"%s\"\n",argnum,argv[argnum]);
>>>
>>>     return EXIT_SUCCESS;
>>>   }
>>>
>>>
>>> Simple program, wot? Just prints argc, and each given argument
>>>
>>>   18:55 $ cc -o Args -mtune=native -Wall -std=c99 -pedantic Args.c
>>>
>>> Compiles clean to C99 standards
>>>
>>>   18:55 $ Args '*'
>>>   argc == 2
>>>   argv[0] -> "Args"
>>>   argv[1] -> "*"
>>>
>>> Oops.... Passed * as argument, got * as argument.
>>
> I tried your program, and I got 125 arguments:
>
>   ...$ gcc c.c -oc
>   ...$ ./c
>   argc == 125
>   ...

If you had run the program exactly as you show it, you would have gotten
no arguments (argc==1).  I'll bet you actually ran
    ./c *
The * is expanded by the shell to a list of file names; there's
nothing the program can do about it.  That's just something you
have to be aware of.  (I won't argue about whether the behavior is
a good idea.)

> (How did you fix it so that you don't have to type "./" which drives me 
> up the wall?)

You can do that by adding the current directory, ".", to $PATH -- but I
strongly suggest *not* doing that.  If you must, be sure to add it to
the end of $PATH, not the beginning.  Otherwise you run the risk of
running arbitrary commands that happen to be in the current directory.
(Imagine you're in a directory containing a script called "ls" that does
something nasty.)

I'm sorry that typing "./" drives you up the wall; my honest advice is
to get used to it.

[...]

> I said it was a Linux quirk. And while it may be possible to disable it 
> (you said you did it temporarily, but didn't see how, unless you mean 
> what you called the 'permanent' disablement), I don't see that as an 
> answer. If you disable it, then a whole load of other things that depend 
> on it will stop working, such as 'ls'.

I hadn't even realized you could disable globbing; I probably knew about
it at some po, but I've never wanted to use it.

My own approach, and the one I recommend, is simply to be aware that *
expands to a list of file names, and to quote it if I want a literal *
character.  And of course to be aware of the other expansion rules.

If you insist on disabling and reenabling globbing, if you're using bash
you can do it with these commands:

    set -o noglob   # disable globbing
    set +o noglob   # re-enable globbing

Again, I don't recommmend this (and I won't argue about the ugly
syntax).

[...]

-- 
Keith Thompson (The_Other_Keith) kst-u@mib.org  <http://www.ghoti.net/~kst>
Working, but not speaking, for JetHead Development, Inc.
"We must do something.  This is something.  Therefore, we must do this."
    -- Antony Jay and Jonathan Lynn, "Yes Minister"

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[command line arguments] more elegant solution ?? Dexterr <dejangru@gmail.com> - 2016-12-11 07:56 -0800
  Re: [command line arguments] more elegant solution ?? Ben Bacarisse <ben.usenet@bsb.me.uk> - 2016-12-11 16:47 +0000
    Re: [command line arguments] more elegant solution ?? Dexterr <dejangru@gmail.com> - 2016-12-11 09:16 -0800
      Re: [command line arguments] more elegant solution ?? Dexterr <dejangru@gmail.com> - 2016-12-11 09:26 -0800
        Re: [command line arguments] more elegant solution ?? Ben Bacarisse <ben.usenet@bsb.me.uk> - 2016-12-11 19:05 +0000
          Re: [command line arguments] more elegant solution ?? Dexterr <dejangru@gmail.com> - 2016-12-11 11:15 -0800
            Re: [command line arguments] more elegant solution ?? Dexterr <dejangru@gmail.com> - 2016-12-11 11:53 -0800
              Re: [command line arguments] more elegant solution ?? Ben Bacarisse <ben.usenet@bsb.me.uk> - 2016-12-11 20:03 +0000
                Re: [command line arguments] more elegant solution ?? Dexterr <dejangru@gmail.com> - 2016-12-11 12:26 -0800
                Re: [command line arguments] more elegant solution ?? Dexterr <dejangru@gmail.com> - 2016-12-11 12:33 -0800
                Re: [command line arguments] more elegant solution ?? Ben Bacarisse <ben.usenet@bsb.me.uk> - 2016-12-11 20:33 +0000
                Re: [command line arguments] more elegant solution ?? Dexterr <dejangru@gmail.com> - 2016-12-11 12:35 -0800
                Re: [command line arguments] more elegant solution ?? "James R. Kuyper" <jameskuyper@verizon.net> - 2016-12-11 16:06 -0500
                Re: [command line arguments] more elegant solution ?? Dexterr <dejangru@gmail.com> - 2016-12-11 13:11 -0800
                Re: [command line arguments] more elegant solution ?? Dexterr <dejangru@gmail.com> - 2016-12-11 13:20 -0800
                Re: [command line arguments] more elegant solution ?? Dexterr <dejangru@gmail.com> - 2016-12-11 13:25 -0800
                Re: [command line arguments] more elegant solution ?? Ben Bacarisse <ben.usenet@bsb.me.uk> - 2016-12-11 21:32 +0000
                Re: [command line arguments] more elegant solution ?? Dexterr <dejangru@gmail.com> - 2016-12-11 13:44 -0800
                Re: [command line arguments] more elegant solution ?? Dexterr <dejangru@gmail.com> - 2016-12-11 13:47 -0800
                Re: [command line arguments] more elegant solution ?? Ben Bacarisse <ben.usenet@bsb.me.uk> - 2016-12-11 21:56 +0000
                Re: [command line arguments] more elegant solution ?? Dexterr <dejangru@gmail.com> - 2016-12-11 14:04 -0800
                Re: [command line arguments] more elegant solution ?? Robert Spanjaard <spamtrap@arumes.com> - 2016-12-11 23:07 +0100
                Re: [command line arguments] more elegant solution ?? Dexterr <dejangru@gmail.com> - 2016-12-11 14:15 -0800
                Re: [command line arguments] more elegant solution ?? Robert Spanjaard <spamtrap@arumes.com> - 2016-12-11 23:32 +0100
                Re: [command line arguments] more elegant solution ?? jameskuyper@verizon.net - 2016-12-11 14:42 -0800
                Re: [command line arguments] more elegant solution ?? Dexterr <dejangru@gmail.com> - 2016-12-11 14:52 -0800
                Re: [command line arguments] more elegant solution ?? Dexterr <dejangru@gmail.com> - 2016-12-11 14:40 -0800
                Re: [command line arguments] more elegant solution ?? jameskuyper@verizon.net - 2016-12-11 14:55 -0800
                Re: [command line arguments] more elegant solution ?? "James R. Kuyper" <jameskuyper@verizon.net> - 2016-12-11 19:44 -0500
                Re: [command line arguments] more elegant solution ?? Richard Heathfield <rjh@cpax.org.uk> - 2016-12-11 23:20 +0000
                Re: [command line arguments] more elegant solution ?? Dexterr <dejangru@gmail.com> - 2016-12-11 15:28 -0800
                Re: [command line arguments] more elegant solution ?? jameskuyper@verizon.net - 2016-12-11 16:28 -0800
      Re: [command line arguments] more elegant solution ?? Ben Bacarisse <ben.usenet@bsb.me.uk> - 2016-12-11 18:57 +0000
  Re: [command line arguments] more elegant solution ?? Barry Schwarz <schwarzb@dqel.com> - 2016-12-11 10:04 -0800
    Re: [command line arguments] more elegant solution ?? Dexterr <dejangru@gmail.com> - 2016-12-11 11:25 -0800
  Re: [command line arguments] more elegant solution ?? BartC <bc@freeuk.com> - 2016-12-11 18:29 +0000
    Re: [command line arguments] more elegant solution ?? Dexterr <dejangru@gmail.com> - 2016-12-11 11:25 -0800
    Re: [command line arguments] more elegant solution ?? Ben Bacarisse <ben.usenet@bsb.me.uk> - 2016-12-11 20:30 +0000
      Re: [command line arguments] more elegant solution ?? BartC <bc@freeuk.com> - 2016-12-11 23:43 +0000
        Re: [command line arguments] more elegant solution ?? Lew Pitcher <lew.pitcher@digitalfreehold.ca> - 2016-12-11 19:02 -0500
          Re: [command line arguments] more elegant solution ?? Lew Pitcher <lew.pitcher@digitalfreehold.ca> - 2016-12-11 19:13 -0500
            Re: [command line arguments] more elegant solution ?? BartC <bc@freeuk.com> - 2016-12-12 00:55 +0000
              Re: [command line arguments] more elegant solution ?? BartC <bc@freeuk.com> - 2016-12-12 01:02 +0000
                Re: [command line arguments] more elegant solution ?? Keith Thompson <kst-u@mib.org> - 2016-12-11 19:02 -0800
                Re: [command line arguments] more elegant solution ?? BartC <bc@freeuk.com> - 2016-12-12 11:50 +0000
                Re: [command line arguments] more elegant solution ?? Ben Bacarisse <ben.usenet@bsb.me.uk> - 2016-12-12 13:46 +0000
                Re: [command line arguments] more elegant solution ?? BartC <bc@freeuk.com> - 2016-12-12 14:43 +0000
                Re: [command line arguments] more elegant solution ?? Ben Bacarisse <ben.usenet@bsb.me.uk> - 2016-12-12 22:09 +0000
                Re: [command line arguments] more elegant solution ?? Keith Thompson <kst-u@mib.org> - 2016-12-12 08:58 -0800
              Re: [command line arguments] more elegant solution ?? Lew Pitcher <lew.pitcher@digitalfreehold.ca> - 2016-12-11 20:06 -0500
              Re: [command line arguments] more elegant solution ?? jameskuyper@verizon.net - 2016-12-11 17:37 -0800
              Re: [command line arguments] more elegant solution ?? Keith Thompson <kst-u@mib.org> - 2016-12-11 18:59 -0800
        Re: [command line arguments] more elegant solution ?? Ben Bacarisse <ben.usenet@bsb.me.uk> - 2016-12-12 02:47 +0000
  Re: [command line arguments] more elegant solution ?? Dexterr <dejangru@gmail.com> - 2016-12-11 15:11 -0800
  Re: [command line arguments] more elegant solution ?? Dexterr <dejangru@gmail.com> - 2016-12-12 00:25 -0800
  Re: [command line arguments] more elegant solution ?? Dexterr <dejangru@gmail.com> - 2016-12-12 00:27 -0800
    Re: [command line arguments] more elegant solution ?? Barry Schwarz <schwarzb@dqel.com> - 2016-12-12 01:01 -0800
      Re: [command line arguments] more elegant solution ?? Dexterr <dejangru@gmail.com> - 2016-12-12 09:42 -0800
        Re: [command line arguments] more elegant solution ?? "James R. Kuyper" <jameskuyper@verizon.net> - 2016-12-12 13:58 -0500
        Re: [command line arguments] more elegant solution ?? Barry Schwarz <schwarzb@dqel.com> - 2016-12-12 14:18 -0800

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