LinuxQuestions.org - how to stop a bash script by pressing a key?

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how to stop a bash script by pressing a key?

Hi i want to know how to stop this loop by pressing a key, and if possible how to start it again with a keystroke.

Code:

#!/bin/bash



PORT=$(($RANDOM))





WID=`xdotool search --name "xxxxxxxxx" | head -1`

xdotool windowactivate $WID



while :



 do



 xdotool sleep .$PORT

 xdotool sleep 4

 xdotool type 7





done

Ctrl+Z will stop the process. You can resume it by using the fg command.

In general, a process can be stopped and resumed by sending the SIGSTOP and SIGCONT signals to the process.

naw dude. it doesnt work

Yes it does. Unless the xdotool is intercepting signals and ignoring them, which is always possible. IIRC, Ctrl+Z sends SIGTSTP which can be caught by a process and thus ignored, whereas SIGSTOP cannot be caught by a process.

okay so how to i code for it to send sigstop by pressing a key?

you can use the command stty -a to check how it is set.
you will get something like this:

Code:

intr = ^C; quit = ^\; erase = ^?; kill = ^U; eof = ^D; eol = M-^?; eol2 = M-^?; swtch = M-^?; start = ^Q;

stop = ^S; susp = ^Z; rprnt = ^R; werase = ^W; lnext = ^V; flush = ^O; min = 1; time = 0;

-parenb -parodd cs8 hupcl -cstopb cread -clocal -crtscts

-ignbrk brkint -ignpar -parmrk -inpck -istrip -inlcr -igncr icrnl ixon -ixoff -iuclc ixany imaxbel iutf8

opost -olcuc -ocrnl onlcr -onocr -onlret -ofill -ofdel nl0 cr0 tab0 bs0 vt0 ff0

isig icanon iexten echo echoe echok -echonl -noflsh -xcase -tostop -echoprt echoctl echoke

see man stty and you will see susp defines that event:

Code:

 susp CHAR

              CHAR will send a terminal stop signal

therefore you need to execute stty susp <your char> if you want to modify it.