sed '/sshd.*pam_unix.*mlo_root/d' tfile

This is a command using the `sed` utility, which is a stream editor used for performing basic text transformations on an input stream (a file or input from a pipeline).

The command performs the following operations:

1. `/sshd.*pam_unix.*mlo_root/d`: This is a pattern that matches lines in the input stream (in this case, the file `tfile`) that contain the text "sshd", followed by any characters, followed by "pam_unix", followed by any characters, followed by "mlo_root".
2. `d`: The `d` command tells `sed` to delete any lines that match the specified pattern.

So, in effect, this command will remove all lines from the file `tfile` that contain the specified text pattern.