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expressing an 8-bit ASCII code
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expressing an 8-bit ASCII code
#3
EOT is handled by the pty emulation. the terminal program just sends byte value 4 to the pty emulation. it is that emulation that converts it to end-of-file. the shell gets the EOF. Today's shells require several EOF events. Classical shells will exit upon just one such event. that exit by the shell sends SIGCHLD to the terminal. or the terminal gets EOF from the side of the PTY it's reading to get shell session output. then the terminal window closes. same action. same effect. now days just type in the shell command "exit" or hold Ctrl+D to let it repeat.

on IBM mainframes, in VM/CP, i found a bug where any "ASCII" terminal doing EOT followed rapidly by BREAK would cause the entire system to freeze requiring a reboot (IPL). the terminal did not even need to be logged in so anyone could dial up the mainframe if they had ASCII dial up and freeze the whole system. once i got the source code, i wrote a patch to fix the bug and sent it to IBM. they accepted it. the new effect took that particular terminal offline and gave the main operator a message of what happened.
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Messages In This Thread
expressing an 8-bit ASCII code - by Skaperen - Jan-15-2020, 12:43 AM
RE: expressing an 8-bit ASCII code - by DeaD_EyE - Jan-15-2020, 09:01 AM
RE: expressing an 8-bit ASCII code - by Skaperen - Jan-16-2020, 01:39 AM

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