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Date: Thu, 1 Nov 2012 14:01:00 -0400
Message-ID: <CA+sc5mkySs10Tg7iCJrFifRGjPe==rQ=kEk+oCAJPO_NiiTcqw@mail.gmail.com>
Subject: Re: Command line arguments
From: Earnie Boyd <earnie AT users DOT sourceforge DOT net>
To: cygwin AT cygwin DOT com
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On Thu, Nov 1, 2012 at 1:54 PM, Brian Wilson wrote:
>> > % >${1}, ${2}, etc.  Also, you may want to read up on the getopts
>> > command as a % >way to process command line arguments. % Technically,
>> > the {}'s are not needed. You can access them with $1, $2, ... %
>> > "/path/to/$1.save/dir" but not "/path/to/$1save/dir" you'd need the
>> > {} % (i.e. "/path/to/${1}save/dir" because otherwise the shell would
>> > be % looking for "1save" as an env variable name.
>>
>> ... except that environment variables cannot begin with numbers :-)
>>
>
> True, but that won't keep the system from trying to interpret the string as
> a variable and erroring out on something a novice might easily write.
>

Actually, I started to state this as well then I tried it.  To my
surprise ``echo $1save'' echoed the contents of $1 followed by the
string save.

> I got in the habbit of always using the "{}" (even if they aren't absolutely
> necessary) to avoid such issues on general principal.

A generally good habit to learn.  It helps to prevent the WTF moments.

-- 
Earnie
-- https://sites.google.com/site/earnieboyd

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