What is the different between 2>&1 and 2>&1 &

The 2>&1 will write standard output and standard errors to a file. While it is processing, the command line will not be available. The shell will wait for the process to complete before letting you enter anything into the command line again. The 2>&1 & will also write standard output and standard errors to a file. The extra & means to execute the process in the background so the command line is still available while it is processing. You can use an & after almost anything to execute it as a background process.

Cara thanks a lots would you mind giving some somment on the following Commands #1 rsh pc1 /tmp/test >>/tmp/test.log 2>&1 & #2 rsh pc1 /tmp/test >>/tmp/test.log "2>&1 &" If i ran #1 , it failed, if i ran #2 , it success thanks!!!