....o xdb.c: In function ‘xdb_open’: xdb.c:171:21: error: ‘LOCK_EX’ undeclared (first use in this function) xdb.c:171:21: note: each undeclared identifier is reported only once for each function it appears in xdb.c: In function ‘xdb_create’: xdb.c:213:20: error: ‘LOCK_EX’ undeclare...