File-open mode flags

When you use files for simple-large-object data, also set the loc_oflags field of the locator structure. The loc_oflags field is of type integer and it contains the host-system file-open mode flags.

These flags determine how the file is to be accessed once it is opened:
  • LOC_RONLY is a mask for read-only mode. Use this value when you insert a simple large object into a file.
  • LOC_WONLY is a mask for write-only mode. Use this value when you select a simple large object into a file and you want each selected simple large object to write over any existing data.
  • LOC_APPEND is a mask for write mode. Use this value when you select a simple large object into a file and you want to append the value to the end of the file.