Hi World,

I have files which I've pulled off of 8mm tape with dd using the conversion to ascii option (from ebcdic) as follows:

dd if=/dev/rmt/$1n of=$file ibs=8k conv=ascii

This works fine except that the file created is not line-terminated correctly and when viewed in nedit for example, the entire file is all in one line.
Nedit allows changing the wrap but it doesn't get it quite the way it should be and doesn't save the changes (hangs) when trying to save large-ish files with the option to ad line-breaks where wrapped.

I've tried changing block sizes and also re-running dd on the file with an unblock and block option to no avail.

Seems to be platform independent (Solaris and cygwin give same results)

Any other ideas much appreciated.
Bryan.

I know nothing about ebcdic, but according to this, it has carriage return (CR = 0x0d (same as ascii of course)), newline (NL = 0x15), and linefeed (LF, 0x25).

I've no idea which of these characters ebcdic uses as an end-of-line marker, but whatever it is (I assume you know, or can figure it out from the files), you can easily convert it (or them) to the ascii newline that unix uses.

For example, if it uses the NL character (0x15), then

should do it (note that this will do in-place replacement, so you might want to leave out the -i until you're sure it works...).

edit:
Oops, you'll probably need to add the g flag to make perl do a global replacement (i.e. 's/\x15/\n/g'), since there will probably be more than one per "line".

Thanks a lot for this reply I'll check it out.

I've made some progress with dd:

dd if=/dev/rmt/$1n of=$file cbs=80 ibs=1024k conv=unblock,aciii

but this doesn't work all the time as tapes are written with different cbs values and seldom is this recorded.
What's also odd is that sometimes you need unblock,ascii and for other files you reverse this to ascii,unblock. Couldn't see this anywhere in man or info.
Changing the cbs (convert bytes size) changes the width (number of characters per line but it's still hit and miss to get it to look as it should. Mostly miss at this stage.
How does one determine the cbs value for data on tape?
I know you can use dd to determine the block size by extracting one block with count=1 and checking its size but don't know how to do this for cbs.

Rgds,
Bryan.

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