@FULL[filename[,path]] : Returns the full path and filename of a file. Filename must be in quotes if it contains white space or special characters. On an LFN drive, the returned filename may contain white space or other special characters. To avoid problems which could be caused by these characters, quote the returned name before you pass it to other commands. See the notes under Variable Functions for additional details.
If filename is quoted, the returned filename will also be quoted (if necessary).
The optional path argument specifies the path name to use to create the name. The path can include relative path operators like "...\".
Note: The @FULL function makes no assumption about the existence of a file or directory. The filename parameter can be any string and the function will attempt to turn it into a fully qualified "volume + path + name" specification, whether that full reference exists or not.
Examples:
cdd c:\windows
echo %@full[explorer.exe]
C:\Windows\explorer.exe
echo "%@full[.]"
"C:\Windows"
echo "%@full["\Program Files"]"
"C:\Program Files"