Check if the BGZF end-of-file (EOF) marker is present
@param fp BGZF file handler opened for reading
@return 1 if the EOF marker is present and correct;
2 if it can't be checked, e.g., because fp isn't seekable;
0 if the EOF marker is absent;
-1 (with errno set) on error
Check if the BGZF end-of-file (EOF) marker is present
@param fp BGZF file handler opened for reading @return 1 if the EOF marker is present and correct; 2 if it can't be checked, e.g., because fp isn't seekable; 0 if the EOF marker is absent; -1 (with errno set) on error