Files with GIL extension can be found as SGML documents. Probably no longer used format.
There is one other file type using
the GIL file extension!
.gil - GroupMail field mapping file
What is gil file? How to open gil files?
The GIL file extension is related to some variant of SGML documents. Most likely very rare or obsolete.
Enter any file extension without dot (e.g. pdf)
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