! ISMBUG.BAS --- bug in XCALL IREAD (use with ISMBUG.CMD)
! IREAD does not wait for record if an ISAM file is opened WAIT'RECORD
! Bob Fowler, Applied Systems Research, 1994-Oct-17

! To demonstrate problem:
!   (1) execute ISMBUG.CMD first
!   (2) RUN ISMBUG.RUN on JOB1 to add new key
!   (3) RUN ISMBUG.RUN on JOB1 to lock new key
!   (4) RUN ISMBUG.RUN on JOB2 to attempt lock on new key
! Step (4) should halt and wait for JOB1, but instead returns ISMERR=29

! Other pertinent notes:
! --- Chris Hunter has IREAD.SBR patch, so that it works with BASIC 1.4
! --- leave for Mike Talbutt at AM via AMTEC
! --- did IREAD "break" in AMOS 2.2(451)-9?  earlier?  always this way?

	MAP1 ISMCHN,F,6,		10
	MAP1 ISMKEY,S,5,		"ABCDE"
	MAP1 RELKEY,F,6
	MAP1 ISM'READSPCLOCK,F,6,	-1
	MAP1 ISMBUF,S,100,		"ABCDE"
	MAP1 ISMERR,F,6

	OPEN #ISMCHN,"ISMBUG",INDEXED,100,RELKEY,WAIT'FILE,WAIT'RECORD

	PRINT "LOOK UP KEY"
	ISAM #ISMCHN, 1, ISMKEY
	IF ERF(ISMCHN) = 0 THEN GOTO EXISTS
! 1st time through this program - JOB1 creates data record
	IF ERF(ISMCHN) # 33 THEN PRINT "ERF"; ERF(ISMCHN) : END
	PRINT "ADDING KEY"
	ISAM #ISMCHN, 5, ISMKEY
	WRITEL #ISMCHN, ISMBUF
	ISAM #ISMCHN, 3, ISMKEY
	END

EXISTS:
	PRINT "LOCK KEY"
	XCALL IREAD, ISMCHN, ISMBUF, ISMERR, ISM'READSPCLOCK
! 3rd time through this program - JOB2 does NOT wait for JOB1 to let go
	PRINT "ISMERR"; ISMERR
! 2nd time through this program - JOB1 reads/locks record and halts for ...
	INPUT "Hit return to continue ... ", ISMERR
	END