Re: Ideas for v2.1

Aaron Ucko (UCKO@vax1.rockhurst.edu)
Fri, 14 Jun 1996 09:10:47 -0600 (CST)


>>> > driver in full working order. So can't we just replace "Ok.\n" with
>>> > "\r\e[K", which will wipe the message off the screen *if* the test
>>> > is successful.
>>>
>>> But these escape sequences would also go to the log files, which
>>> is probably not good...
>>
>>It would a simple matter to _NOT_ log escape sequences, since
>>printk would already have to detect them in the first place.
>>The escape code just shouldn't be put in the buffer.
>
>No, it would probably be quite tricky. I'm sure someone will jump on
>me if I'm wrong, but as I see it the escape sequence is generated by
>the compiler as a string literal and passed in the original call to
>printk(). printk() sorts out logging and buffering as necessary, and
>by default (with no klogd) will output the string verbatim to the
>console device. The console device then interprets any escape
>sequences as necessary. You really don't want to have to *interpret*
>the sequences anywhere other than in the console code, and this is
>basically what you have to do to figure out how many characters after
>the initial escape code \033 need to be ignored.
>
>To strip it out you have to do one of the following:
>
> Write an intelligent log viewer that correctly detects and removes VT
> escape sequences. Tricky.

Not _that_ tricky. Read
file://cs.utk.edu/pub/shuford/terminals/how_to_emulate.txt and you'll see
that the syntax is pretty regular.

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