rb_io_modestr_oflags  132 include/ruby/io.h int rb_io_modestr_oflags(const char *modestr);
rb_io_modestr_oflags 6427 io.c           	oflags = rb_io_modestr_oflags(StringValueCStr(vmode));
rb_io_modestr_oflags 1579 process.c                      flags = INT2NUM(rb_io_modestr_oflags(StringValueCStr(flags)));