Timothy Luoma asked,
| Is there any way to detect NULLs using procmail, and possibly convert them
| to something else or simply delete them?
Procmail can handle nulls; the problem is that your editor may be unable to
insert a null into your .procmailrc.
A condition to detect the presence of a null, if you can edit a null into
your .procmailrc, is easy enough to write:
* HB ?? ^@
[where ^@ is an actual null, not caret-at]. If your editor allows you to
enter a character #255 but not a null, you can do this:
* HB ?? [^A-\255]
where ^A is a ctrl-A [not caret-A] and \255 is an actual character #255 (not
Finally, if your editor won't let you enter a character #255 either, but it
allows you to filter a single line, you might be able to enter some tempo-
rary character for the character #255 and then run that line through tr
to change it to a #255.
All told, you might want to make the recipe unconditional, since it won't
hurt a message that contains no nulls.
The action line to get rid of nulls is another question. If your local
version of tr hates nulls, then it drops them automatically:
if it respects nulls, you'll need to tell it the options to remove them:
| tr -d \\0