Perl Script Is Hanging With Tomcat Server

Question

I am running a Perl script in which I need to start a tomcat server. After starting the server I need to execute a different linux command.

In the Perl script after starting tomcat it isn't coming out to the next line as tomcat sever is running..

system("tomcat.sh run >log.txt");
system("ls");

I tried to open the server in different terminal. But control remains there itself.

system("xterm", "-hold", "-e", " tomcat.sh run");

I tried exec in place of system but the behaviour is same.

score 3 · Answer 1 · edited May 23 '17 at 12:27

3

If you use the single string version of system then you can append an & to run your command in the background:

system("tomcat.sh run >log.txt &");

Should do the trick.

I also found a similar question here

edited May 23 '17 at 12:27

Community

1
1

answered May 30 '14 at 16:13

John C

4,276
2
17
28

Thanks Jonhn, But i tried using this '&' earlier, But same problem.. :( – smriti May 31 '14 at 05:49
That's very weird. I tested it. Are you trying to do it with xterm? – John C May 31 '14 at 10:30
i am using system("tomcat.sh run >log.txt &"); – smriti May 31 '14 at 13:09
Have a look at this [answer](http://superuser.com/questions/410472/bin-sh-cant-access-tty-job-control-turned-off-error-when-running-shellcode). It might help you. – John C May 31 '14 at 23:47
Thanks a lot again, I used fork() command to control the process.. – smriti Jun 01 '14 at 06:26

score 2 · Accepted Answer · edited May 23 '17 at 12:27

2

This is because system blocks until the process finishes. I'm not sure on how to deal with such situation, you might fork it, close STDIN before you run external process etc. Instead of system, you might try IPC::System::Simple, which handles a lot of platform-specific details for you, or modules like IPC::Run or IPC::Open3.

Similar to your issue: Why does my jzip process hang when I call it with Perl's system?

edited May 23 '17 at 12:27

Community

1
1

answered May 30 '14 at 15:28

Chankey Pathak

21,187
12
85
133

1

I used fork() command to control the processes. Thanks Chankey, – smriti Jun 01 '14 at 06:30

Perl Script Is Hanging With Tomcat Server

2 Answers2