What is a file with a name! I mean?

Question

My computer (RedHat 6 Linux) recently created several empty files with the following name:

!

Yes, one exclamation point. I wonder what, whatever, on Linux will create files of this name? Perhaps more likely this is due to some recent (unsuccessful) packages that I tried to run on my local high-performance computing system. For reference, I use PBS to send jobs to a high-performance computing system.

I am using tcsh

Answer 1

pbs , -S /bin/tcsh ( , tcsh /bin/.

script:

#PBS -S /bin/tcsh