_PC_SYNC_IO       913 ext/etc/constdefs.h #if !defined(_PC_SYNC_IO)
_PC_SYNC_IO       915 ext/etc/constdefs.h #  define _PC_SYNC_IO _PC_SYNC_IO
_PC_SYNC_IO      1487 ext/etc/constdefs.h #if defined(_PC_SYNC_IO)
_PC_SYNC_IO      1488 ext/etc/constdefs.h     rb_define_const(mod, "PC_SYNC_IO", INTEGER2NUM(_PC_SYNC_IO));