From: Dave Burns <tburns@...>
Date: 2008-03-14T09:30:03+09:00
Subject: Re: script runs ok alone, broken pipe when piped to head?

On Mar 13, 1:04 pm, Mark Bush <m...@bushnet.org> wrote:
> Dave Burns wrote:
> >  so I piped it to head and it bombs:
>
> >   ruby -rubygems excelparse.rb stuff.xls|head
> >  Row: 0 Cell: 0> Dispapp
> >  Row: 0 Cell: 1> Iprc
> >  Row: 0 Cell: 2> UH tag
> >  Row: 0 Cell: 3> Weight
> >  Row: 0 Cell: 4> Tags removed
> >  Row: 0 Cell: 5> Disk removed or wiped
> >  Row: 1 Cell: 0> 80118
> >  Row: 1 Cell: 1> 1173
> >  Row: 1 Cell: 2> 961SU
> >  Row: 2 Cell: 0> 80118
> >  excelparse.rb:19:in `write': Broken pipe (Errno::EPIPE)
>
> The "head" command reads and prints the first 10 lines of input (by
> default), then closes its input and exits.
>
> Your script is thus having it's output stream closed which it isn't
> expecting.  The broken pipe is to be expected.
>

So to get my script to act like a responsible command line citizen,
I'd need to insert some error handling and return normally when the
pipe breaks, right?

Thanks for the info.
Dave