[howto][svn] Quickly revert a commit

There are more flexible ways, but here is a quick way to simply revert one commit.

svn merge -c -[R]

R = Revision.

So reverting commit 5400 would be:

svn merge -c -5400

Don't forget that dash before the revision.

Taken from:

 http://stackoverflow.com/questions/13330011/how-do-i-revert-an-svn-commit

[VirtualBox][howto] Map COM port higher than COM9

According to https://www.virtualbox.org/ticket/6421

Trying to map a COM port higher than COM9 in virtual box will result in this error:

(VERR_FILE_NOT_FOUND).
Details:
Fehlercode: E_FAIL (0x80004005)
Komponente: Console
Interface: IConsole {6375231a-c17c-464b-92cb-ae9e128d71c3}

The solution is to give the full path:

COM12 would be \\.\COM12.