0, 1, and 2 represent the standard file descriptors in POSIX operating systems. A file descriptor is a system reference to a file or socket.
- 0 -> stdin
- 1 -> stdout
- 2 -> stderr
/dev/null indicates a empty device.
> is used for output redirection. >> is used for appending the redirected output to a file
< is used for redirecting the input
& is used to tell the shell to run the command as a job in the background.
/opt/dbeaver/dbeaver > /dev/null/ 2 >&1
2>&1 indicates stderr is redirected to stdout, here & infront 1 indicates
1 is not a file name but a file descriptor.
hence the script dbeaver stdout and stderr are both redirected to null
device, indicating they are discarded.
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