This variable affects the behavior of indexed and relative files when
reversing direction after reading past the beginning or end of a file. Normally, if
you perform a series of READ NEXTs that reach to the end of the file (returning
file status "10"), a subsequent READ PREVIOUS returns the last record in the
file. The file pointer's position after each READ NEXT is just past the end of
the last record. Similarly, reading past the beginning of the file and then
doing a READ NEXT returns the first record in the file.
Under ICOBOL, these conditions produce different results. The record returned
by the READ PREVIOUS is the second-to-last record in the file, and the record
returned by the READ NEXT is the second record in the file. Essentially, when
a series of READs passes either end of the file, the record pointer remains on
the first or last record.
Setting ICOBOL_FILE_SEMANTICS to "1" (or true, on, yes) causes the runtime to emulate ICOBOL's
handling. This is useful when porting ICOBOL programs to ACUCOBOL-GT. This
option is only effective in programs that have been compiled for ACUCOBOL-85 2.0, or
later. The default value is "0" (off, false, no).