[Undocumented] Print

[carlos]

Hello. Doing some experiments I found a undocumented feature of print command. I'm sure that someone found this before, and really I did this many time ago, but today I found that this feature is not documented.

The documentation says that in /D:Printer parameter you need specify a PRINTER dispositive like LPT1,LPT2,LPT3,COM1,COM2,COM3,COM4 or network printer like \\ServerName\ShareName

But I found that you can specify a FILE on the printer.
This added a \0x0C character at the end of file.

Example:

Code: Select all

Echo.Hello>src.txt
Print /D:foo.out src.txt >NUL
notepad foo.out

or:

Code: Select all

Echo.Hello>src.txt
Print /D:MYFILE src.txt >NUL
notepad MYFILE

And this added a new utility feature: Added the \0x0C at the end of file and use \0x0C as character of end of file marker.

Also, create a file with the \0x0C character only:

Code: Select all

Type NUL > EMPTY.TXT
Print /D:CHAR.TXT EMPTY.TXT >NUL

Note:
If the the destination file exists print not overwrite the content, it not print to it. Is neccesary delete the destination file first.

[foxidrive]

It copies binary files to the foo.out too, and maintains the file except for the added last byte.

[carlos]

I added a note about if the destination file exists.