Re: So that's what they're for.

From: Tim Haynes (usenet-20031128_at_stirfried.vegetable.org.uk)
Date: 11/28/03

  • Next message: Stephane CHAZELAS: "Re: So that's what they're for." 
    Date: Fri, 28 Nov 2003 11:28:40 +0000

    "Chris F.A. Johnson" <c.fa.johnson@rogers.com> writes:

    > First, don't call external commands when there are internal
    > commands or syntax to accomplish the same thing. E.g.:
    >
    > NEWSIG=$(( $RANDOM * $NUMSIGS / 32767 ))

    Of course, this might not be readily portable to all shells the user wants.
    `expr' and/or `bc' might be worthwhile playing with.

    > Second, when external commands are necessary, don't call more
    > of them than absolutely necessary:
    >
    > NUMSIGS=`grep ^# ~/.siglist | wc -l`

    Says you, when you could've suggested

     NUMSIGS=$(grep -c "^#" ~/.siglist)

    instead ;8)

    ~Tim 

    -- 
No more sun, No more wind                   |piglet@stirfried.vegetable.org.uk
Only this strange feeling                   |http://spodzone.org.uk/cesspit/
Living without moving                       |
  • Next message: Stephane CHAZELAS: "Re: So that's what they're for."

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