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ping like windows dos ping

From: ian@john-richard.co.uk (Ian Peattie)
Subject: Re: set ping default count?
Date: Thu, 01 Feb 2001 11:02:03 GMT
References: <3a772c79.110495317@news.kiva.net>
<3A7732F5.7CCE413F@aplawrence.com>
<95a7sr$b36$1@nnrp1.deja.com> 

In article <95a7sr$b36$1@nnrp1.deja.com>, Robert Carnegie <rja.carnegie@mailexcite.com> wrote:
>In article <3A7732F5.7CCE413F@aplawrence.com>,
>  Tony Lawrence <tony@aplawrence.com> wrote:

>> You need a shell script named "ping" in /bin (which precedes
>> /usr/bin in PATH) that does:
>>
>> /usr/bin/ping -c 5 $*
>>
>> Watch out that this doesn't break some other script, though..

>A version that accepts a default _and_ lets you override
>it with an explicit "-c" parameter earns bonus points,
>I suppose; without hands on at the moment, I think that
>might call for a script, that can parse the command line
>for a "-c" parameter whose value will be stored to a
>variable initialised to 5, and then throw that and the
>other parameters at the real "ping" - which I wouldn't
>expect to be cooperative when handed two "-c" parameters,
>a default and a real one, although trying it out won't
>do any harm.

Bonus points to Tony, then, as his suggestion does that. Most commands will 
use getopt(S), or similar, internally to loop though their arguments, which 
will normally cause the last appearance of a particular argument to override 
any previous ones. So if you run:

   ping -c5 -c4 -c3 -c2 -c1 www.sco.com

The -c1 will be the option that ping uses.

Generally commands will accept multiple redundant arguments without complaint. 
You could, if you had too much time on your hands, sit and type in:

  l -t -t -t -t -t -t -t -t -t -t -t -t -t -t -t 

and it will function equivalently to 'l -t'.  

However, some commands do attach special meaning to the same argument being 
used multiple times. For example, to enable debugging, a command might produce 
one level of debugging when run as 'cmd -d' but a higher level when run as 
'cmd -d -d'.

   Ian.

-- 
Ian Peattie                             ian@john-richard.co.uk
Edinburgh, Scotland.

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