smbget:tldr:2a178

This command is using the smbget tool to download a file from a server using the SMB (Server Message Block) protocol.

Let's break down its components:

• ${smb:--server-share-file}: This is a parameter variable that specifies the server, share, and file information to download. It is enclosed in {} and preceded by $, which indicates it is a variable. The format for this parameter is server/share/filepath.
• --user ${username%password}: This parameter specifies the username to authenticate with the server. The ${username%password} portion is using parameter substitution to remove the suffix %password from the value stored in the username variable. It means that the username variable contains both the username and password, separated by the string "password". By removing the suffix, only the username is extracted.

Putting it all together, the command is using smbget to download the file specified by ${smb:--server-share-file} from the server defined in the smb variable. It also uses the --user parameter to authenticate with the server using the username extracted from the username variable.