ref: c2762df06f75459cb52510d21db6424ed9b1184a dir: /sys/src/ape/cmd/expr/mkfile/
APE=/sys/src/ape <$APE/config TARG=expr OFILES=y.tab.$O YFILES=expr.y HFILES=regexp.h BIN=$APEBIN </sys/src/cmd/mkone YFLAGS=-S CFLAGS=-B -c