add directory study

study/linux-travel/MINIX-1.5/1.5/Source/commands/m4/Hash.m4

@@ -0,0 +1,17 @@
+dnl	This probably will not run on any m4 that cannot
+dnl	handle char constants in eval.
+dnl
+changequote(<,>) define(HASHVAL,99) dnl
+define(hash,<eval(str(substr($1,1),0)%HASHVAL)>) dnl
+define(str,
+	<ifelse($1,",$2,
+		<str(substr(<$1>,1),<eval($2+'substr($1,0,1)')>)>)
+	>) dnl
+define(KEYWORD,<$1,hash($1),>) dnl
+define(TSTART,
+<struct prehash {
+	char *keyword;
+	int   hashval;
+} keytab[] = {>) dnl
+define(TEND,<	"",0
+};>) dnl