A pointer to a loaded network if successful, NULL in case of an error.
FUNCTION
This function operates as a shell around the fscanf_network function.
If the filename is not found, .Z is added and the existence of the file
is checked again. If a file with either the original name or the .Z name
exists, a pipe is set up to the zcat shell command and fscanf_network
is called.
NOTE
The zcat command must be available in the user's search path. Reading
compressed files does not work under Turbo-C / MS-DOS, since this combination
does not support pipes.
There may be a problem with portability using too long filenames. When
a network is written in compressed form, .Z is added to the filename.
If this filename already contains an extension, the file will not be
properly named under MS-DOS.
