Re: Extracting the 4th word of the first line in a file - is there a more elegant solution?

[Peter Stephenson <Peter.Stephenson@xxxxxxx>]

On Fri, 18 May 2012 15:16:54 +0200
Ronald Fischer <ynnor@xxxxx> wrote:
> # $1 is the filename
> line=$(head -n 1 $1)
> field=${lin[(w)4]}

It depends a bit how big the file is.  If it's small, it's very easy,
and involves no extra processes (the "$(<...)" is optimised to a read):

  field=${$(<$1)[4]}

The disadvantage is that reads the entire file into memory first.  It's
hard to think of a way that avoids that that doesn't use an auxiliary
process, but apart from that it's still relatively straightforward
within zsh:

  field=${$(read -e <$1)[4]}

This reads a single line from the file and echoes it instead of
assigning it to a parameter.  You might want "read -qe" if the file
contains backslashes.

You can do it without an auxiliary process, but with a local variable,
which is probably more efficient and the best compromise:

  read -A line <$1
  field=$line[4]

-- 
Peter Stephenson <pws@xxxxxxx>            Software Engineer
Tel: +44 (0)1223 692070                   Cambridge Silicon Radio Limited
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