On Thu, 22 Jan 2004 19:21:25 GMT, Fabio Giannotti <fabiog@venmar.com>
wrote:

>
>
>> -----Original Message-----
>> From: listmaster@xenitec.on.ca
>> [mailto:listmaster@xenitec.on.ca] On Behalf Of Scott McMillan
>> Sent: Thursday, January 22, 2004 12:53 PM
>> To: distribution@xenitec.on.ca
>> Subject: Losing variables after IFS
>>
>>
>> Hello all,
>>
>> I hope someone can point me in the right direction. I have
>> the following script burned to CD-ROM using mkisofs v1.14 and
>> cdrecord 1.10 - both precompiled SCO Openserver binaries
>> running on OSR5.0.6:
>>
>> # more test
>> #!/bin/sh
>> cd /tmp
>> COPY="copy -omv"
>> $COPY /mnt/tst1.txt sdm1
>> IFS=``
>> $COPY /mnt/tst1.txt sdm2
>>
>> I mount the CD on my SCO system, and run the 'test' script:
>> # ls -l /tmp
>> total 0
>> # mount /dev/cd0 /mnt
>> # ls -l /mnt
>> total 4
>> -rwxr-xr-x 1 root sys 92 Jan 22 08:21 test
>> -rw-rw-rw- 1 root sys 29 Jan 22 08:20 tst1.txt
>>
>> # /mnt/test
>> copy file /mnt/tst1.txt
>> /mnt/test: copy -omv: not found
>>
>> # ls -l /tmp
>> total 2
>> -rw-rw-rw- 1 root sys 29 Jan 22 08:20 sdm1
>>
>> As you can see, the first copy works fine, but my IFS=
>> definition seems to 'break' my $COPY variable definition.
>> This ONLY occurs when running the script on CD - Other
>> installations that extract from tape/floppy (using tar) to
>> the HD perform everything as expected.
>>
>> Can someone explain to me what the IFS=`` does to my $COPY?
>> I'm not sure if it's due to the shell (Bourne), something to
>> do with the mkisofs/cdrecord I'm using, etc.
>>
>Scott,
>
>That's really odd. I just tried it on my system and it has the exact same
>effect, even though I'm not doing anything with a CD. That is, I just
>created a little script and ran it from root and "broke" exactly the same
>way.
>
>That is, setting it to null with either double quotes, single quotes or back
>quotes causes the same behavior. Basically, after setting IFS to null the
>system sees the entire variable "copy -vom" as one string, not two seperate
>strings seperated by a space.
>
>So, you can't set IFS to null and have it work.
>
>You can see what setting IFS is doing by looking at the following:
>IFS=";"
>COPY="copy;-vom"
>$copy file1 file2
>
>Good luck,
>Fabio

Hi Fabio,

Well, after reading your reply, I went back to my install scripts (the
above is just to recreate the problem) and found that you are right,
it's NOT just on CDs. My real scripts are finished with all variables
BEFORE the IFS= line, so the issue never showed itself. Sorry for
that bit of mis-information.

But I'm not really sure I understand your example above. Is IFS
_inserting_ it's value into my COPY variable, in place of a space? If
so, I've been misinterpreting its use for awhile now, and better get
back to RTFM!

Thanks for your help.


Scott McMillan