weird behavior with timeout(1) in a script

[Solène Rapenne]

hi

I found a weird behavior trying to use timeout(1) in a script with
interactive commands. My use case is to ask for unlocking /home
from /etc/rc.local but continue if I don't type it in time.

this is working:

        timeout 2s less /etc/fstab

the same command isn't working from a script, running it get stuck and
can't be stopped with ctrl+C

        #!/bin/sh
        timeout 2s less /etc/fstab

However, using timeout with a non interactive command in a script
doesn't create troubles

in the issue case, a ktrace gives the following last lines, but I don't
know how to interpret them

 21097 timeout  PSIG  SIGCHLD caught handler=0xb1d715d6b00 
mask=0x86007<SIGHUP|SIGINT|SIGQUIT|SIGALRM|SIGTERM|SIGCHLD>
 21097 timeout  RET   sigsuspend -1 errno 4 Interrupted system call
 21097 timeout  CALL  sigreturn(0x7f7ffffe3540)
 21097 timeout  RET   sigreturn JUSTRETURN
 21097 timeout  CALL  kbind(0x7f7ffffe3868,24,0xd30add790970a7bd)
 21097 timeout  RET   kbind 0
 21097 timeout  CALL  wait4(WAIT_ANY,0x7f7ffffe39f4,0<>,0)