awk help needed

[Jamon Camisso]

Chris F.A. Johnson wrote:
> On Sun, 19 Jul 2009, Jamon Camisso wrote:
> 
>> Giles Orr wrote:
>>> 2009/7/18 Alex Beamish <talexb-Re5JQEeQqe8AvxtiuMwx3w at public.gmane.org>:
>>>> On Sat, Jul 18, 2009 at 11:46 AM, Giles Orr<gilesorr-Re5JQEeQqe8AvxtiuMwx3w at public.gmane.org> wrote:
>>>>> By way of introduction: I'm finally, finally trying to get a new
>>>>> edition of the Bashprompt HOWTO out there.  This will probably result
>>>>> in me posting a lot of detailed and mildly weird questions to this
>>>>> list.  This is the first.
>>>>>
>>>>> The intention of this script is to figure out how much space the files
>>>>> in the current directory take up.  There are about a million ways to
>>>>> do this - and yes, I know that "ls -l" spits out a "total" line: I
>>>>> don't know what it's totaling, but my math has never agreed with it
>>>>> ... feel free to explain though.  I decided that I'd like to do this
>>>>> as much in awk as possible since it does decimal math (unlike bash)
>>>>> and it's certainly the easiest way to do the text parsing.  I've tried
>>>>> bc as well, but you have to use other utility programs to parse and
>>>>> split the input for it.
>>>> Sorry, but I usually use the du command for this.
>>>>
>>>>  root at music:/etc/init.d# du -h .
>>>>  504K    .
>>>>
>>>> Sometimes I want to know how heavy an entire tree is, so I use
>>>>
>>>>  $ du -sh foo
>>>>
>>>> The 'h' argument does intelligent size management, so shows K, M and G.
>>>
>>> I would love to use "du" because initially it seems like precisely the
>>> right tool ... but I want only the sum of the sizes of the files in
>>> the current directory, and "du" is by default recursive (which also
>>> makes it painfully slow to return, not a good thing for something
>>> incorporated into a Bash prompt).  If it's possible to stop "du" from
>>> recursing, I'll use it immediately - but that looks difficult to
>>> impossible.  Any thoughts?
>>>
>>> Thanks to everyone else who answered too: it all helped.  It certainly
>>> sounds like piping into "awk" is the way to go rather than trying to
>>> write a self-contained "awk" script.
>>>
>>
>> Try this:
> 
>   DON'T.
> 
>> #!/bin/bash
>>
>> i=0 j=0 k=0
>> echo -n "Enter directory: "
>> read dir
>> for i in `ls $dir`
> 
>     Not only is ls unnecessary, but it will cause the script to fail
>     if any filenames contain spaces or other pathological characters.
>     Use:
> 
> for i in "$dir"/*
> 
>>  do
>>    if [ -f $i ]; then
>>      j=`du -s $i |awk '{print $1}'`
>>      k=`expr $k + $j`
>>    fi
>>  done
>> echo $k
> 
> 

Interesting, I started with for i in * but that barfs on stuff too. 
Suppose since I don't have an files I can see with spaces in their names 
(pathological hatred for such names), it appears to work correctly for me :)

Jamon
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