Execute combine multiple linux commands in one lin

问题:

I am trying to merge multiple linux commands in one line to perform deployment operation. For example

cd /my_folder
rm *.jar
svn co path to repo
mvn compile package install

回答1:

If you want to execute each command only if the previous one succeeded, then combine them using the && operator:

cd /my_folder && rm *.jar && svn co path to repo && mvn compile package install

If one of the commands fails, then all other commands following it won't be executed.

If you want to execute all commands regardless of whether the previous ones failed or not, separate them with semicolons:

cd /my_folder; rm *.jar; svn co path to repo; mvn compile package install

In your case, I think you want the first case where execution of the next command depends on the success of the previous one.

You can also put all commands in a script and execute that instead:

#! /bin/sh
cd /my_folder \
&& rm *.jar \
&& svn co path to repo \
&& mvn compile package install

(The backslashes at the end of the line are there to prevent the shell from thinking that the next line is a new command; if you omit the backslashes, you would need to write the whole command in a single line.)

Save that to a file, for example myscript, and make it executable:

chmod +x myscript

You can now execute that script like other programs on the machine. But if you don't place it inside a directory listed in your PATH environment variable (for example /usr/local/bin, or on some Linux distributions ~/bin), then you will need to specify the path to that script. If it's in the current directory, you execute it with:

./myscript

The commands in the script work the same way as the commands in the first example; the next command only executes if the previous one succeeded. For unconditional execution of all commands, simply list each command on its own line:

#! /bin/sh
cd /my_folder
rm *.jar
svn co path to repo
mvn compile package install

回答2:

I've found that using ; to separate commands only works in the foreground. eg :

cmd1; cmd2; cmd3 & - will only execute cmd3 in the background, whereas cmd1 && cmd2 && cmd3 & - will execute the entire chain in the background IF there are no errors.

To cater for unconditional execution, using parenthesis solves this :

(cmd1; cmd2; cmd3) & - will execute the chain of commands in the background, even if any step fails.

回答3:

You can separate your commands using a semi colon:

cd /my_folder;rm *.jar;svn co path to repo;mvn compile package install

Was that what you mean?

回答4:

If you want to execute all the commands, whether the previous one executes or not, you can use semicolon (;) to separate the commands.

cd /my_folder; rm *.jar; svn co path to repo; mvn compile package install

If you want to execute the next command only if the previous command succeeds, then you can use && to separate the commands.

cd /my_folder && rm *.jar && svn co path to repo && mvn compile package install

In your case, the execution of consecutive commands seems to depend upon the previous commands, so use the second example i.e. use && to join the commands.

回答5:

To run them all at once, you can use the pipe line key "|" like so:

$ cd /my_folder | rm *.jar | svn co path to repo | mvn compile package install

回答6:

cd /my_folder && rm *.jar && svn co path to repo && mvn compile package install

回答7:

What is the utility of an only one Ampersand? This morning, I made a launcher in the XFCE panel (in Manjaro+XFCE) to launch 2 passwords managers simultaneously:

sh -c "keepassx && password-gorilla"
or
sh -c "keepassx; password-gorilla"

But it does not work as I want. I.E., the first app starts but the second starts only when the previous is closed :-/

However, I found that (with only one ampersand):

sh -c "keepassx & password-gorilla"

and it works as I want now...

回答8:

You can use as the following code;

cd /my_folder && \
rm *.jar && \
svn co path to repo && \
mvn compile package install

It works...

回答9:

I find lots of answer for this kind of question misleading

Modified from this post: https://www.webmasterworld.com/linux/3613813.htm

The following code will create bash window and works exactly as a bash window. Hope this helps. Too many wrong/not-working answers out there...

            Process proc;
            try {
                //create a bash window
                proc = Runtime.getRuntime().exec("/bin/bash");
                if (proc != null) {
                       BufferedReader in = new BufferedReader(new InputStreamReader(proc.getInputStream()));
                       PrintWriter out = new PrintWriter(new BufferedWriter(new OutputStreamWriter(proc.getOutputStream())), true);
                       BufferedReader err = new BufferedReader(new InputStreamReader(
                       proc.getErrorStream()));
                       //input into the bash window
                       out.println("cd /my_folder");
                       out.println("rm *.jar");
                       out.println("svn co path to repo");
                       out.println("mvn compile package install");
                       out.println("exit");
                       String line;
                        System.out.println("----printing output-----");
                          while ((line = in.readLine()) != null) {
                             System.out.println(line);
                          }
                          while((line = err.readLine()) != null) {
                             //read errors
                          }
                          proc.waitFor();
                          in.close();
                          out.close();
                          err.close();
                          proc.destroy();
                }

            } catch (IOException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            } catch (InterruptedException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            }