我正在为应用程序编写一个bash包装器.该包装器负责更改用户,运行软件和记录其输出.
我也希望它传播SIGINT信号.
到目前为止,这是我的代码：
#!/bin/bash
set -e; set -u
function child_of {
ps --ppid $1 -o "pid" --no-headers | head -n1
}
function handle_int {
echo "Received SIGINT"
kill -int $(child_of $SU_PID)
}
su myuser -p -c "bash /opt/loop.sh 2>&1 | tee -i >(logger -t mytag)" &
SU_PID=$!
trap "handle_int" SIGINT
wait $SU_PID
echo "This is the end."
我的问题是,当我向这个包装器发送一个SIGINT时,handle_int被调用但是脚本结束了,而我希望它继续等待$SU_PID.
有没有办法捕获int信号,做一些事情,然后阻止脚本终止？
最佳答案
你有一个问题：在Ctrl-C之后,“这就是结束.”预计但它永远不会到来,因为脚本已经过早退出.原因是在set -e下运行时wait(意外地)返回非零值.
根据“男子打击”：
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. When bash is waiting for an asynchronous command via the
wait builtin,the reception of a signal for which a trap has been set will cause the wait builtin to return
immediately with an exit status greater than 128,immediately after which the trap is executed.
您应该将set wait包装在set e中,以便在等待异步命令时处理捕获的信号后程序可以继续运行.
像这样：
# wait function that handles trapped signal on asynchronous commands.
function safe_async_wait {
set +e
wait $1 # returns >128 on asynchronous commands
set -e
}
#...
safe_async_wait $SU_PID
