A common programming technique is to create a temporary file and immediately unlink() it. This leaves the file (and its space) available for the duration of the program but automatically causes its removal when the program using it terminates. One advantage is that no epilog (cleanup) code is necessary to write. To determine if you have a process holding an unlinked file open, do:
lsof -a +L1 /ebstest01db
or
lsof +D /ebstest01db +L1
Look for any files with an NLINK value of zero (0). These would be files with a zero link count that will vanish when the last process terminates. The SIZE/OFFSET column will offer the character size of the file in question.
sles02:/ # lsof -a +L1 /ebstest01db
COMMAND PID USER FD TYPE DEVICE SIZE/OFF NLINK NODE NAME
oracle 9605 ebstest01 256u REG 8,33 40255488 0 3678213 /oradata/data_old/cntrl01.dbf (deleted)
oracle 9605 ebstest01 257u REG 8,33 40255488 0 5775361 /oradata/data_old/cntrl02.dbf (deleted)
oracle 9605 ebstest01 258u REG 8,33 40255488 0 9969665 /oradata/data_old/cntrl03.dbf (deleted)
oracle 9605 ebstest01 259uW REG 8,33 4294975488 0 2629640 /oradata/data_old/system01.dbf (deleted)
oracle 9605 ebstest01 260uW REG 8,33 4294975488 0 3678209 /oradata/data_old/system02.dbf (deleted)
oracle 9605 ebstest01 261uW REG 8,33 4294975488 0 3678210 /oradata/data_old/system03.dbf (deleted)
oracle 9605 ebstest01 262uW REG 8,33 4294975488 0 1597441 /oradata/data_old/system04.dbf (deleted)
oracle 9605 ebstest01 263uW REG 8,33 4294975488 0 1597448 /oradata/data_old/system05.dbf (deleted)
oracle 9605 ebstest01 264uW REG 8,33 4294975488 0 1597449 /oradata/data_old/system06.dbf (deleted)
oracle 9605 ebstest01 265uW REG 8,33 4294975488 0 1597450 /oradata/data_old/system07.dbf (deleted)
oracle 9605 ebstest01 266uW REG 8,33 4294975488 0 1597451 /oradata/data_old/system08.dbf (deleted)
oracle 9605 ebstest01 267uW REG 8,33 4632879104 0 4931624 /oradata/data_old/sysaux01.dbf (deleted)
oracle 9605 ebstest01 268uW REG 8,33 4554235904 0 4931599 /oradata/data_old/sysaux02.dbf (deleted)
And now kill the 3605 process.