Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP Path: utzoo!linus!decvax!harpo!seismo!hao!hplabs!sri-unix!dbj.rice@rand-relay From: dbj.rice@rand-relay@sri-unix.UUCP Newsgroups: net.unix-wizards Subject: Re: sh and sigtstp problem. Message-ID: <3750@sri-arpa.UUCP> Date: Tue, 2-Aug-83 17:38:17 EDT Article-I.D.: sri-arpa.3750 Posted: Tue Aug 2 17:38:17 1983 Date-Received: Fri, 5-Aug-83 11:56:48 EDT Lines: 28 From: Dave JohnsonFrom: JPAYNE@BBNG ... I tried Pausing emacs under /bin/sh and emacs simply returned immediately and repainted the screen. ... Perhaps the kernel refuses to send signals greater than 16, when the new mechanism hasn't been used, so that old programs don't break. From: chris@umcp-cs ... I took a look into the kernel code and came up with ... nothing ... There may be something special in psignal ... The reason this happens is simple: SIGTSTP is ignored by login, which is inherited by the /bin/sh, and is then inherited by the Emacs. When emacs decides that you're trying to do a pause-emacs, it sends itself a SIGTSTP. Since this is ignored in the case that you're running the Emacs from /bin/sh (without a csh behind it), the signal does nothing. When emacs wakes back up from the pause (which in this case is immediate since the pause was ignored), it redraws the screen. The reason this behaves differently when you login to csh instead of sh is that the C-shell sets the action for SIGTSTP back to SIG_DFL when it starts up. Dave Johnson Dept. of Math Science Rice University dbj.rice@Rand-Relay