jlo@pixel.phx.mcd.mot.com (Joe Ortiz) (06/08/89)
We've been tracking down a problem with xterm (R11.2) which results in the apparent hang of the window. The symptoms were that the xterm window would not echo keyboard data, or paste data. Also, the output from commands was not displayed within the xterm window, but redirection of command output to a file or another un-hung window showed the command was being executed. The way I got into this mode was within /bin/sh (not /bin/ksh), I had entered an escape followed by a newline. The result was the xterm finite state machine entered a mode where it was expecting an escape sequence, and not finding a valid one, and thus not displaying any data. All characters to be displayed were thrown away in the IGNORE_STATE. Typing the kill character unhung the window. I know the problem is a function of xterm's vt100 terminal emulation processing, but it seems like there should be some smarts about not waiting indefinitely for an escape sequence, or smarts about not allowing escape sequences greater than the max valid vt100 escape sequence length. Has anybody seen this problem before? Have any fixes been made to xterm?