On Wed, Oct 06, 2010 at 03:58:41PM +0200, Michael Vogt wrote: > > It appears that since a recent upgrade, you can't interrupt apt runs > > anymore. > [..] > > This is a bug in the code, it looks like this is a regression caused > by setting the termios rtt var via "rtt.c_lflag |= ISIG". This fixed > making it possible to background dpkg, but apparently it broke > ctrl-c. Which is odd given that the documentation says that is is used > to enable signals.
Uhm, 1. it is set by default, 2. it indeed enables recognition of signals. I remember disabling it in a program of mine: http://angband.pl/viewvc/kbtin/trunk/user_tty.c?view=markup and after checking again, it does work as in the documentation. Quoting glibc's docs: # -- Macro: tcflag_t ISIG # This bit controls whether the INTR, QUIT, and SUSP characters are # recognized. The functions associated with these characters are # performed if and only if this bit is set. Being in canonical or # noncanonical input mode has no affect on the interpretation of # these characters. # # You should use caution when disabling recognition of these # characters. Programs that cannot be interrupted interactively are # very user-unfriendly. If you clear this bit, your program should # provide some alternate interface that allows the user to # interactively send the signals associated with these characters, # or to escape from the program. With that bit clear, Ctrl-C produces a character 0x03. With it set, it sends SIGINT. I didn't look at the apt code, but there must be more to it than merely setting this flag. -- 1KB // Microsoft corollary to Hanlon's razor: // Never attribute to stupidity what can be // adequately explained by malice. -- To UNSUBSCRIBE, email to [email protected] with a subject of "unsubscribe". Trouble? Contact [email protected]
