Very Computer

AIX 5.2 (ksh)

Hello Everyone,

I have another question pertaining to stty. Here is what I have:

# a.sh
stty intr '^-' susp '^-' dsusp '^-' quit '^-'    # Disable ^C, ^Z, ^Y
and ^\.
/tmp/b.sh
echo "back to a.sh"

# b.sh
echo "inside b.sh...."
stty intr '^c'
sleep 30

After I execute a.sh (and when it is inside b.sh), if I hit Ctrl-C
while it is 'sleeping', I get back to the command prompt. Is there a
way I can prevent that and instead pass the control back to a.sh to the
line after /tmp/b.sh? (in this case, it would be the 'echo' command)

Thanks for any suggestions.
S

2006-06-5, 08:21(-07), Unix-Shell:

Quote:> AIX 5.2 (ksh)

> Hello Everyone,

> I have another question pertaining to stty. Here is what I have:

> # a.sh
> stty intr '^-' susp '^-' dsusp '^-' quit '^-'    # Disable ^C, ^Z, ^Y
> and ^\.
> /tmp/b.sh
> echo "back to a.sh"

> # b.sh
> echo "inside b.sh...."
> stty intr '^c'
> sleep 30

> After I execute a.sh (and when it is inside b.sh), if I hit Ctrl-C
> while it is 'sleeping', I get back to the command prompt. Is there a
> way I can prevent that and instead pass the control back to a.sh to the
> line after /tmp/b.sh? (in this case, it would be the 'echo' command)

[...]

^- is not a character. Maybe your stty ignores it because of
that?

What about stty intr ''

or trap '' INT

--
Stphane

I tried stty intr '', but the behavior is the same. Ctrl-C brings me
back to the command prompt, instead of going back to the echo command
in a.sh.

If I use trap, setting the interrupt in b.sh has no effect. I cannot
Ctrl-C at all.

2006-06-5, 14:20(-07), Unix-Shell:

If you want Ctrl-C to interrup sleep and not the other
foreground processes, you can either do:

trap '' INT

in a.sh (ignore it there):

trap : INT

in b.sh (not ignore it but do nothing, this way, it will still
interrupt "sleep").

Or you can make sure "sleep" is started as a new process group
and that process group is the foreground process group of the
terminal (so that only that only that process group gets the
SIGINT upon the Ctrl-C).

For that, you can add a "set -m" in b.sh, but that will not work
with every shell (for the shell interpreting b.sh).

--
Stphane

You can try this in b.sh:

    trap 'exit 0' INT

It will cause b.sh to exit successfully on SIGINT, so the execution
continues in a.sh.

--
Kenan Kalajdzic

Depends on the implementation, some also and some even only accept
this as notation for <undef>.

I tried trap '' INT in a.sh and trap 'exit 0' INT in b.sh, but it does
not work. I cannot Ctrl-C and interrupt sleep. However, when I do the
same on the command line, it works perfectly:

Quote:> trap '' INT
> trap 'exit 0' INT
> sleep 10

Ctrl-C

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