To copy all hidden dot files using scp in Linux or Unix, you need to include the -r option to copy the directory recursively, and the -a option to preserve the file attributes such as permissions, timestamps, and symbolic links:
scp -r -a user@source_host:/path/to/source/directory/ /path/to/destination/directory/
In this example, user is the username on the source host, source_host is the name or IP address of the source host, and /path/to/source/directory/ and /path/to/destination/directory/ are the paths to the source and destination directories, respectively.
The -r option tells scp to copy the directory recursively, including all its subdirectories and files. The -a option tells scp to preserve the file attributes such as permissions, timestamps, and symbolic links, so that the copied files have the same properties as the original files.
By using these options, scp will copy all hidden dot files in the source directory to the destination directory.