Sorry if this is a known issue or has already been corrected

No need for a response.

VMS/VAX 7.2 GZIP 1.3.12e

Compresses FILE.DAT;1 and FILE.DAT;2 is deleted.

  FILE.DAT;2

  FILE.DAT;1

$ GZIP FILE.DAT;1

$ DIRECTORY FILE.DAT*

  FILE.DAT;1

  FILE.DAT-GZ;1

There are VMS native RMS library routines that will return the fully qualified file specification of an open file.

There are VMS native RMS library routines that will delete a file when it is closed.

Either option it should only delete the input file on success.