[sclug] Bash scripting help needed

[pieter claassen]

Neil,

Check your spaces around the vars in the [ "$1" .... tests. You need
to get the spaces in between the test [ and the variable I believe.
Bash is currently trying to execute a command called '["$1"'

A better test to use I find is [[ which I think is called arithmetic
tests. Here is a good reference.

http://www.ibm.com/developerworks/linux/library/l-bash-test.html

Cheers,
Pieter

On Tue, Apr 21, 2009 at 9:30 PM, Neil Haughton
<haughtonomous at googlemail.com> wrote:
> Hi,
>
> I'm starting out (it had to happen eventually) on a bit of bash scripting.
> It's simple task really, but I want to save myself a bit of repetitive
> labour (as you do).
>
> The trouble is it won't play, and I am stumped. Can anyone point me at the
> error?
>
> The purpose of the script (for your interest) is to concatenate all the
> audio files in a given folder into one big uninterrupted file. If I rip one
> of my classical CDs the music is annoyingly split into 'tracks', which is
> fine for rock or pop, but irritating when the music is intended to be one
> long piece.
>
> My script to deal with this (named audiojoin) is located in /usr/local/bin
> (on my PATH) and I have chmod-ed it to u+rx, and chowned it to be owned by
> me. If I plonk myself in a shell in another directory where the source files
> are and execute the script, I get a series of errors that I do not
> understand.
>
> Here's the script contents:
>
> #! /bin/bash
>
> if ["$1" -eq ""]; then
> echo "Use: command codectype outputfilename"
> exit
> fi
>
> if ["$2" -eq ""]; then
> echo "Use: command codectype outputfilename"
> exit
> fi
>
> echo "codec type=$1"
> echo "output file=$2"
>
> #build a list of the files in the current directory
> fileList=""
> for f in $(ls ./); do
> ?fileList="$fileList \"$f\""
> done
>
> #now join them all together into one big audio file
> `shnjoin -o $1 $fileList`
>
> #rename the result as asked
> mv joined.$1 $2.$1
> #end of script
>
> So I execute it with (say):
>
> $audiojoin flac Act1
>
> and I should end up with all the .flac files in the current directory
> concatenated into a single file called Act1.flac
>
> Here's the console output:
>
> /usr/local/bin/audiojoin: line 3: [flac: command not found
> /usr/local/bin/audiojoin: line 8: [Act1: command not found
> codec type=flac
> output file=Act1
> shnjoin: warning: cannot open non-existent file: ["01.flac"]
> shnjoin: error: could not open file: ["01.flac"]
> mv joined.flac Act1.flac
>
>
> Questions:
>
> 1. Why the two "command not found' messages?
> 2. Why the "cannot open non-existent file" warnings when the files do indeed
> exist in the current directory (from where I launch the command), which by
> the way is in my home folder?
>
> I should add that if I 'echo' the shnjoin line and then copy and paste the
> resulting echoed output at the prompt, it executes correctly - just not from
> the script. eg
>
> shnjoin -o flac "01.flac" "02.flac"
>
> works fine if I do it myself.
>
> It's almost as if the script executes in the context of its own directory,
> not the directory where I launch it, which would explain why it cannot find
> the files listed in the $fileList variable.
>
> Any ideas?
>
> TIA
>
> Neil.
>