IDA Help: set_fixup

set fixup information
     ea        - address to set fixup information about
     type      - fixup type. see get_fixup_target_type()
                 for possible fixup types.
     fixupf    - FIXUPF_... bits
     targetsel - target selector
     targetoff - target offset
     displ     - displacement
returns: none

void set_fixup(long ea, long type, long fixupf, long targetsel, long targetoff, long displ);

The fixupf argument may have the following bits:
fixup is relative to the linear address `base'. Otherwise fixup is
relative to the start of the segment with `sel' selector.
#define FIXUPF_REL         0x0001

target is a location (otherwise - segment).
Use this bit if the target is a symbol rather than an offset from the
beginning of a segment.
#define FIXUPF_EXTDEF      0x0002

fixup is ignored by IDA
  - disallows the kernel to convert operands
  - this fixup is not used during output
#define FIXUPF_UNUSED      0x0004

fixup was not present in the input file
#define FIXUPF_CREATED     0x0008