Welcome to OGeek Q&A Community for programmer and developer-Open, Learning and Share
Welcome To Ask or Share your Answers For Others

Categories

0 votes
325 views
in Technique[技术] by (71.8m points)

bash: start multiple chained commands in background

I'm trying to run some commands in paralel, in background, using bash. Here's what I'm trying to do:

forloop {
  //this part is actually written in perl
  //call command sequence
  print `touch .file1.lock; cp bigfile1 /destination; rm .file1.lock;`;
}

The part between backticks (``) spawns a new shell and executes the commands in succession. The thing is, control to the original program returns only after the last command has been executed. I would like to execute the whole statement in background (I'm not expecting any output/return values) and I would like the loop to continue running.

The calling program (the one that has the loop) would not end until all the spawned shells finish.

I could use threads in perl to spawn different threads which call different shells, but it seems an overkill...

Can I start a shell, give it a set of commands and tell it to go to the background?

See Question&Answers more detail:os

与恶龙缠斗过久,自身亦成为恶龙;凝视深渊过久,深渊将回以凝视…
Welcome To Ask or Share your Answers For Others

1 Reply

0 votes
by (71.8m points)

I haven't tested this but how about

print `(touch .file1.lock; cp bigfile1 /destination; rm .file1.lock;) &`;

The parentheses mean execute in a subshell but that shouldn't hurt.


与恶龙缠斗过久,自身亦成为恶龙;凝视深渊过久,深渊将回以凝视…
OGeek|极客中国-欢迎来到极客的世界,一个免费开放的程序员编程交流平台!开放,进步,分享!让技术改变生活,让极客改变未来! Welcome to OGeek Q&A Community for programmer and developer-Open, Learning and Share
Click Here to Ask a Question

...