Trap “break” not working while read command is being called
I have this bash-written hangman game for a school project, and currently I am trying to replace the ctrl-c exit command for a while loop break, so the user goes back from the actual game to the categories selection menu.
The code I am currently using is:
trap "break" SIGINT
and inside the while loop:
read CHAR
Everything works fine when a text is printed in the loop and also when the sleep command is running, but when the algorithm is at the read command, pressing ctrl-c just inputs "^C" on the console.
bash read trap sigint
edited Dec 16 at 11:50
Rui F Ribeiro
38.9k1479129
asked Apr 3 at 0:58
Marcos Rios
62
add a comment |
I have this bash-written hangman game for a school project, and currently I am trying to replace the ctrl-c exit command for a while loop break, so the user goes back from the actual game to the categories selection menu.
The code I am currently using is:
trap "break" SIGINT
and inside the while loop:
read CHAR
Everything works fine when a text is printed in the loop and also when the sleep command is running, but when the algorithm is at the read command, pressing ctrl-c just inputs "^C" on the console.
bash read trap sigint
edited Dec 16 at 11:50
Rui F Ribeiro
38.9k1479129
asked Apr 3 at 0:58
Marcos Rios
62
Please update your post to show all the steps you have taken. Include as much of the script as possible to help troubleshoot the issue.
– kemotep
Apr 3 at 2:01
add a comment |
I have this bash-written hangman game for a school project, and currently I am trying to replace the ctrl-c exit command for a while loop break, so the user goes back from the actual game to the categories selection menu.
The code I am currently using is:
trap "break" SIGINT
and inside the while loop:
read CHAR
Everything works fine when a text is printed in the loop and also when the sleep command is running, but when the algorithm is at the read command, pressing ctrl-c just inputs "^C" on the console.
bash read trap sigint
edited Dec 16 at 11:50
Rui F Ribeiro
38.9k1479129
asked Apr 3 at 0:58
Marcos Rios
62
I have this bash-written hangman game for a school project, and currently I am trying to replace the ctrl-c exit command for a while loop break, so the user goes back from the actual game to the categories selection menu.
The code I am currently using is:
trap "break" SIGINT
and inside the while loop:
read CHAR
Everything works fine when a text is printed in the loop and also when the sleep command is running, but when the algorithm is at the read command, pressing ctrl-c just inputs "^C" on the console.
bash read trap sigint
bash read trap sigint
edited Dec 16 at 11:50
Rui F Ribeiro
38.9k1479129
asked Apr 3 at 0:58
Marcos Rios
62
edited Dec 16 at 11:50
Rui F Ribeiro
38.9k1479129
asked Apr 3 at 0:58
Marcos Rios
62
edited Dec 16 at 11:50
Rui F Ribeiro
38.9k1479129
edited Dec 16 at 11:50
Rui F Ribeiro
38.9k1479129
edited Dec 16 at 11:50
Rui F Ribeiro
38.9k1479129
38.9k1479129
asked Apr 3 at 0:58
Marcos Rios
62
asked Apr 3 at 0:58
Marcos Rios
62
asked Apr 3 at 0:58
Marcos Rios
62
62
Please update your post to show all the steps you have taken. Include as much of the script as possible to help troubleshoot the issue.
– kemotep
Apr 3 at 2:01
add a comment |
Please update your post to show all the steps you have taken. Include as much of the script as possible to help troubleshoot the issue.
– kemotep
Apr 3 at 2:01
Please update your post to show all the steps you have taken. Include as much of the script as possible to help troubleshoot the issue.
– kemotep
Apr 3 at 2:01
Please update your post to show all the steps you have taken. Include as much of the script as possible to help troubleshoot the issue.
– kemotep
Apr 3 at 2:01
add a comment |
1 Answer
1
active
oldest
votes
If bash is waiting for a command to complete and receives a signal for which a trap has been set, the trap will not be executed until the command completes.
That is the reason why the read is not interrupted.
The ^C is not printed by the shell but by the terminal due to the setting echoctl. If you execute stty -echoctl then it does not appear.
answered Apr 3 at 1:39
Hauke Laging
55.8k1285133
add a comment |
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1 Answer
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active
oldest
votes
1 Answer
1
active
oldest
votes
active
oldest
votes
active
oldest
votes
If bash is waiting for a command to complete and receives a signal for which a trap has been set, the trap will not be executed until the command completes.
That is the reason why the read is not interrupted.
The ^C is not printed by the shell but by the terminal due to the setting echoctl. If you execute stty -echoctl then it does not appear.
answered Apr 3 at 1:39
Hauke Laging
55.8k1285133
add a comment |
If bash is waiting for a command to complete and receives a signal for which a trap has been set, the trap will not be executed until the command completes.
That is the reason why the read is not interrupted.
The ^C is not printed by the shell but by the terminal due to the setting echoctl. If you execute stty -echoctl then it does not appear.
answered Apr 3 at 1:39
Hauke Laging
55.8k1285133
add a comment |
If bash is waiting for a command to complete and receives a signal for which a trap has been set, the trap will not be executed until the command completes.
That is the reason why the read is not interrupted.
The ^C is not printed by the shell but by the terminal due to the setting echoctl. If you execute stty -echoctl then it does not appear.
answered Apr 3 at 1:39
Hauke Laging
55.8k1285133
If bash is waiting for a command to complete and receives a signal for which a trap has been set, the trap will not be executed until the command completes.
That is the reason why the read is not interrupted.
The ^C is not printed by the shell but by the terminal due to the setting echoctl. If you execute stty -echoctl then it does not appear.
answered Apr 3 at 1:39
Hauke Laging
55.8k1285133
answered Apr 3 at 1:39
Hauke Laging
55.8k1285133
answered Apr 3 at 1:39
Hauke Laging
55.8k1285133
answered Apr 3 at 1:39
Hauke Laging
55.8k1285133
55.8k1285133
add a comment |
add a comment |
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Please update your post to show all the steps you have taken. Include as much of the script as possible to help troubleshoot the issue.
– kemotep
Apr 3 at 2:01