Change the file names of two files
 

Hi.
I want to be able to easily change the file names of two files in bash shell.

Example: filname1.txt switch names with filname2.txt.
In this way, I want to transfer the contents of filname1.txt to filname2.txt and content of filname2.txt to filname1.txt
But I can not figure out how this can be done.

The easiest way is to use an interim filename:

mv filename1.txt filename.tmp
mv filename2.txt filename1.txt
mv filename.tmp filename2.txt