Re: Non-printable Bytes in Variable Data

[Martin McCormick <martin@dc.cis.okstate.edu>]

	Hmm.

Bill Marcum writes:
> How does your script create the file names?

It initially gets it from the index number of the audio file
that cdda2wav generates plus the Tracktitle= line that appears in
one of the  audio_NN.inf files.  In this case, audio_01.inf which
contains many informational lines about the disk:

\#created by cdda2wav 2.01.01a01_linux_2.6.8.1-vs1.9.2_i686_i686 12/04/06 20:37:15
\#

	The song titles come from lines like:

Tracktitle=	'Joy to the World'
Tracknumber=	1

	In the shell script I wrote, I get the title with the
following code:


songtitle=`grep Tracktitle= $srcpath/audio_$track_no.inf \
| sed -e 's/^[[:space:]]*//g' \
| sed 's/Tracktitle=//g'  \
|sed 's/'\''//g'`

	All that isolates the string enclosed in the ''s and
knocks off any spaces at the beginning if there are any.

	The last line of sed eats the ' or single quotes.

	I get the track number by extracting it from the digits
in the trackxx.cdda.wav file names and putting it in to a
variable called $track_no.  What I wanted to do was have the two
digits of track_no precede the file name string like 01Joy to the
World.  That's where it gets weird.

songfilename="$track_no$songtitle.mp3"

	That should concatonate both strings in to one, but there
is a blank between them.

> Try this:
> echo "$songfilename" | od -to1z

	Great minds think alike.  Before I read your response, I
tried exactly that except od -tx1 which gives a hex dump.  od
-to1z  gives an octal dump and shows

0000000 112 157 171 040 164 157 040 164 150 145 040 127 157 162 154 144  >Joy to the World<
0000020 056 155 160 063 012                                              >.mp3.<

for the song title string and it shows that the $track_no
variable only contains 01 and nothing odd.

	Both the echo commands show a newline at the end, but
nothing else was there that shouldn't be there.  I do think it is
strange that the ? appears in the script-generated parms sent to
bladeenc, but not the time I ran it manually with "'s around the
output file name string.

	As I sit here, I am thinking of one more thing to try.
If it works, I will post that it did, but I haven't really had a
great discovery yet.

	Again, thanks.