caveat

接收Fax的程序

/*
** (c) 1992 Uwe C. Schroeder, Anwendungssysteme , Augsburg, Germany
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** This is a alpha release, which means, that there are still several
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(1)
I would like to implement the fax receive mode #B1. Now a multipage
fax is received in one single file. This is bad for using a conversion
utility like g3toxxx or fax2tiff, because these programs can't handle
faximiles longer than 2 pages. So it would be convenient to have
several files containing the pages.

(2)
Further, for sending faxes, the connect-string should be parsed for
the resolution (low, high). The matching resolution should be sent.
Therefore I will first create two files (one low, one high) in the spool
directory and then send the appropriate file.

(3)
There is a bug in the receive function (rcv.c). The software can't receive
the disconnect string correct. This is a fas problem, because fas ignores
incoming data after carrier low.On my system the modem sends the disconnect
message between carrier low and reenabling the tty. Therefor several characters
get lost. This will be fixed with (1)

(4)
It's bad, that the spooler locks the tty. Therefor a dial out will
fail, or won't work correctly. This is because the voice mode doesn't
rise the carrier, so a real getty isn't possible. My way to get around
this is the vfax -x0 (-x1) call, that will release the tty (reenable the tty).
This won't be useful for a automatic dial in (like uucp). It's ok for
manual terminal sessions (with cu or xc etc.)