Port to C99/C23. Correct usage of timeval in utmp, rename reserved keywords
Also cast pointers to pointers to signed chars to unsigned chars
It's that or redo multiple functions from unsigned chars to signed chars
and unsigned chars with implicit cast worked so far.
https://bugs.gentoo.org/919459
https://bugs.gentoo.org/946205
--- a/date/date.c
+++ b/date/date.c
@@ -141,6 +141,7 @@
 	const char wtmpxfile[] = "/var/log/wtmp";
 	time_t newtime;
 	struct timeval	tv;
+	struct timeval before_tv, after_tv;
 
 	memset(&before, 0, sizeof before);
 	memset(&after, 0, sizeof after);
@@ -150,14 +151,19 @@
 	strcpy(after.ut_line, "new time");
 	if ((newtime = timeop(op)) == (time_t)-1)
 		badconv();
-	gettimeofday(&before.ut_tv, NULL);
+	gettimeofday(&before_tv, NULL);
+	before.ut_tv.tv_sec = before_tv.tv_sec;
+	before.ut_tv.tv_usec = before_tv.tv_usec;
 	tv.tv_sec = newtime;
 	tv.tv_usec = 0;
 	if (settimeofday(&tv, NULL) < 0) {
 		fprintf(stderr, "%s: no permission\n", progname);
 		exit(1);
 	}
-	gettimeofday(&after.ut_tv, NULL);
+	gettimeofday(&after_tv, NULL);
+	after.ut_tv.tv_sec = after_tv.tv_sec;
+	after.ut_tv.tv_usec = after_tv.tv_usec;
+
 #ifdef	__linux__
 	system("/sbin/hwclock -w >/dev/null 2>&1");
 #endif	/* __linux__ */
--- a/nawk/main.c
+++ b/nawk/main.c
@@ -168,18 +168,18 @@
 	}
 	/* hold leading name=val arguments until just after BEGIN */
 	if (posix && argc > 1 && isclvar(argv[1])) {
-		start_delayed = &argv[0];
+		start_delayed = (unsigned char **)&argv[0];
 		do {
 			argv[0] = argv[1];
 			argv++;
 		} while (--argc > 1 && isclvar(argv[1]));
-		after_delayed = &argv[0];
+		after_delayed = (unsigned char **)&argv[0];
 	}
 	compile_time = 1;
 	argv[0] = cmdname;	/* put prog name at front of arglist */
 	dprintf( ("argc=%d, argv[0]=%s\n", argc, argv[0]) );
-	arginit(argc, argv);
-	envinit(envp);
+	arginit(argc, (unsigned char **)argv);
+	envinit((unsigned char **)envp);
 	yyparse();
 	if (fs)
 		*FS = tostring(qstring(fs, '\0'));
--- a/nawk/run.c
+++ b/nawk/run.c
@@ -61,9 +61,9 @@
 Cell	*tmps;
 
 static Cell	truecell	={ OBOOL, BTRUE, 0, 0, 1.0, NUM };
-Cell	*true	= &truecell;
+Cell	*trueval	= &truecell;
 static Cell	falsecell	={ OBOOL, BFALSE, 0, 0, 0.0, NUM };
-Cell	*false	= &falsecell;
+Cell	*falseval	= &falsecell;
 static Cell	breakcell	={ OJUMP, JBREAK, 0, 0, 0.0, NUM };
 Cell	*jbreak	= &breakcell;
 static Cell	contcell	={ OJUMP, JCONT, 0, 0, 0.0, NUM };
@@ -108,7 +108,7 @@
 	register Node *a;
 
 	if (u == NULL)
-		return(true);
+		return(trueval);
 	for (a = u; ; a = a->nnext) {
 		curnode = a;
 		if (isvalue(a)) {
@@ -148,7 +148,7 @@
 	if (a[0]) {		/* BEGIN */
 		x = execute(a[0]);
 		if (isexit(x))
-			return(true);
+			return(trueval);
 		if (isjump(x))
 			error(MM_ERROR,
 				":44:Illegal break, continue or next from BEGIN");
@@ -174,7 +174,7 @@
 		if(x != 0) { tempfree(x, ""); }
 	}
   ex1:
-	return(true);
+	return(trueval);
 }
 
 struct Frame {
@@ -461,7 +461,7 @@
 
 	x = execute(a[0]);	/* Cell* for symbol table */
 	if (!isarr(x))
-		return true;
+		return trueval;
 	subseplen = strlen((char *)*SUBSEP);
 	growbuf(&buf, &bufsz, CHUNK, NULL, "delete");
 	buf[0] = 0;
@@ -479,7 +479,7 @@
 	freeelem(x, buf);
 	tempfree(x, "");
 	free(buf);
-	return true;
+	return trueval;
 }
 
 Cell *intest(Node **a, int n)
@@ -511,9 +511,9 @@
 	tempfree(ap, "");
 	free(buf);
 	if (k == NULL)
-		return(false);
+		return(falseval);
 	else
-		return(true);
+		return(trueval);
 }
 
 
@@ -557,9 +557,9 @@
 		x->fval = start;
 		return x;
 	} else if ((n == MATCH && i == 1) || (n == NOTMATCH && i == 0))
-		return(true);
+		return(trueval);
 	else
-		return(false);
+		return(falseval);
 }
 
 
@@ -573,22 +573,22 @@
 	tempfree(x, "");
 	switch (n) {
 	case BOR:
-		if (i) return(true);
+		if (i) return(trueval);
 		y = execute(a[1]);
 		i = istrue(y);
 		tempfree(y, "");
-		if (i) return(true);
-		else return(false);
+		if (i) return(trueval);
+		else return(falseval);
 	case AND:
-		if ( !i ) return(false);
+		if ( !i ) return(falseval);
 		y = execute(a[1]);
 		i = istrue(y);
 		tempfree(y, "");
-		if (i) return(true);
-		else return(false);
+		if (i) return(trueval);
+		else return(falseval);
 	case NOT:
-		if (i) return(false);
-		else return(true);
+		if (i) return(falseval);
+		else return(trueval);
 	default:	/* can't happen */
 		error(MM_ERROR, ":55:Unknown boolean operator %d", n);
 	}
@@ -613,18 +613,18 @@
 	tempfree(x, "");
 	tempfree(y, "");
 	switch (n) {
-	case LT:	if (i<0) return(true);
-			else return(false);
-	case LE:	if (i<=0) return(true);
-			else return(false);
-	case NE:	if (i!=0) return(true);
-			else return(false);
-	case EQ:	if (i == 0) return(true);
-			else return(false);
-	case GE:	if (i>=0) return(true);
-			else return(false);
-	case GT:	if (i>0) return(true);
-			else return(false);
+	case LT:	if (i<0) return(trueval);
+			else return(falseval);
+	case LE:	if (i<=0) return(trueval);
+			else return(falseval);
+	case NE:	if (i!=0) return(trueval);
+			else return(falseval);
+	case EQ:	if (i == 0) return(trueval);
+			else return(falseval);
+	case GE:	if (i>=0) return(trueval);
+			else return(falseval);
+	case GT:	if (i>0) return(trueval);
+			else return(falseval);
 	default:	/* can't happen */
 		error(MM_ERROR, ":56:Unknown relational operator %d", n);
 	}
@@ -944,7 +944,7 @@
 		}
 		free(buf);
 	}
-	return(true);
+	return(trueval);
 }
 
 Cell *arith(Node **a, int n)
@@ -1155,7 +1155,7 @@
 		x = execute(a[2]);
 		return(x);
 	}
-	return(false);
+	return(falseval);
 }
 
 Cell *split(Node **a, int nnn)
@@ -1312,7 +1312,7 @@
 		tempfree(x, "");
 		x = execute(a[1]);
 		if (isbreak(x)) {
-			x = true;
+			x = trueval;
 			in_loop--;
 			return(x);
 		}
@@ -1334,7 +1334,7 @@
 		x = execute(a[0]);
 		if (isbreak(x)) {
 			in_loop--;
-			return true;
+			return trueval;
 		}
 		if (isnext(x) || isexit(x) || isret(x)) {
 			in_loop--;
@@ -1371,7 +1371,7 @@
 		x = execute(a[3]);
 		if (isbreak(x)) {		/* turn off break */
 			in_loop--;
-			return true;
+			return trueval;
 		}
 		if (isnext(x) || isexit(x) || isret(x)) {
 			in_loop--;
@@ -1405,7 +1405,7 @@
 			if (isbreak(x)) {
 				tempfree(vp, "");
 				in_loop--;
-				return true;
+				return trueval;
 			}
 			if (isnext(x) || isexit(x) || isret(x)) {
 				tempfree(vp, "");
@@ -1416,7 +1416,7 @@
 		}
 	}
 	in_loop--;
-	return true;
+	return trueval;
 }
 
 static int closefile(const char *a);
@@ -1552,7 +1552,7 @@
 	}
 	if (a[1] != 0)
 		fflush(fp);
-	return(true);
+	return(trueval);
 }
 
 /*ARGSUSED*/
@@ -1694,7 +1694,7 @@
 		tempfree(y, "");
 	}
 	y = execute(a[2]);	/* replacement string */
-	result = false;
+	result = falseval;
 	if (pmatch(pfa, t)) {
 		growbuf(&buf, &bufsize, CHUNK, NULL, "sub");
 		pb = buf;
@@ -1730,7 +1730,7 @@
 							"sub");
 			}
 		setsval(x, buf);
-		result = true;;
+		result = trueval;;
 		free(buf);
 	}
 	tempfree(x, "");
--- a/oawk/awk.def
+++ b/oawk/awk.def
@@ -215,7 +215,7 @@
 #define NPA2	4
 
 extern obj	(*proctab[])(node **, int);
-extern obj	true, false;
+extern obj	trueval, falseval;
 extern int	pairstack[], paircnt;
 
 #define cantexec(n)	(n->ntype == NVALUE)
--- a/oawk/run.c
+++ b/oawk/run.c
@@ -96,8 +96,8 @@
 #define MAXTMP 20
 cell tmps[MAXTMP];
 static cell nullval ={EMPTY,EMPTY,0.0,NUM,0};
-obj	true	={ OBOOL, BTRUE, 0 };
-obj	false	={ OBOOL, BFALSE, 0 };
+obj	trueval	={ OBOOL, BTRUE, 0 };
+obj	falseval	={ OBOOL, BFALSE, 0 };
 
 int chrlen(const char *s);
 int chrdist(const char *s, const char *end);
@@ -125,7 +125,7 @@
 	node *a;
 
 	if (u==(node *)NULL)
-		return(true);
+		return(trueval);
 	for (a = u; ; a = a->nnext) {
 		if (cantexec(a))
 			return(nodetoobj(a));
@@ -156,7 +156,7 @@
 	if (a[0] != NULL) {
 		x = execute(a[0]);
 		if (isexit(x))
-			return(true);
+			return(trueval);
 		if (isjump(x))
 			error(FATAL, "unexpected break, continue or next");
 		tempfree(x);
@@ -173,7 +173,7 @@
 			error(FATAL, "unexpected break, continue or next");
 		tempfree(x);
 	}
-	return(true);
+	return(trueval);
 }
 
 /*ARGSUSED*/
@@ -228,9 +228,9 @@
 	tempfree(x);
 	i = match((struct fa *)a[1], s);
 	if (n==MATCH && i==1 || n==NOTMATCH && i==0)
-		return(true);
+		return(trueval);
 	else
-		return(false);
+		return(falseval);
 }
 
 obj boolop(node **a,int n)
@@ -245,22 +245,22 @@
 	default:
 		error(FATAL, "unknown boolean operator %d", n);
 	case BOR:
-		if (i) return(true);
+		if (i) return(trueval);
 		y = execute(a[1]);
 		i = istrue(y);
 		tempfree(y);
-		if (i) return(true);
-		else return(false);
+		if (i) return(trueval);
+		else return(falseval);
 	case AND:
-		if ( !i ) return(false);
+		if ( !i ) return(falseval);
 		y = execute(a[1]);
 		i = istrue(y);
 		tempfree(y);
-		if (i) return(true);
-		else return(false);
+		if (i) return(trueval);
+		else return(falseval);
 	case NOT:
-		if (i) return(false);
-		else return(true);
+		if (i) return(falseval);
+		else return(trueval);
 	}
 }
 
@@ -283,18 +283,18 @@
 	switch (n) {
 	default:
 		error(FATAL, "unknown relational operator %d", n);
-	case LT:	if (i<0) return(true);
-			else return(false);
-	case LE:	if (i<=0) return(true);
-			else return(false);
-	case NE:	if (i!=0) return(true);
-			else return(false);
-	case EQ:	if (i==0) return(true);
-			else return(false);
-	case GE:	if (i>=0) return(true);
-			else return(false);
-	case GT:	if (i>0) return(true);
-			else return(false);
+	case LT:	if (i<0) return(trueval);
+			else return(falseval);
+	case LE:	if (i<=0) return(trueval);
+			else return(falseval);
+	case NE:	if (i!=0) return(trueval);
+			else return(falseval);
+	case EQ:	if (i==0) return(trueval);
+			else return(falseval);
+	case GE:	if (i>=0) return(trueval);
+			else return(falseval);
+	case GT:	if (i>0) return(trueval);
+			else return(falseval);
 	}
 }
 
@@ -675,7 +675,7 @@
 	obj x;
 
 	if (a[0]==nullstat)
-		x = true;
+		x = trueval;
 	else
 		x = execute(a[0]);
 	if (istrue(x)) {
@@ -703,7 +703,7 @@
 		x = execute(a[2]);
 		return(x);
 	}
-	return(false);
+	return(falseval);
 }
 
 obj aprintf(node **a,int n)
@@ -714,7 +714,7 @@
 	if (a[1]==NULL) {
 		printf("%s", x.optr->sval);
 		tempfree(x);
-		return(true);
+		return(trueval);
 	}
 	redirprint(x.optr->sval, (intptr_t)a[1], a[2]);
 	return(x);
@@ -823,7 +823,7 @@
 		tempfree(x);
 		x = execute(a[1]);
 		if (isbreak(x)) {
-			x = true;
+			x = trueval;
 			return(x);
 		}
 		if (isnext(x) || isexit(x))
@@ -845,7 +845,7 @@
 		}
 		x = execute(a[3]);
 		if (isbreak(x)) {	/* turn off break */
-			x = true;
+			x = trueval;
 			return(x);
 		}
 		if (isnext(x) || isexit(x))
@@ -871,7 +871,7 @@
 			setsval(vp, cp->nval);
 			x = execute(a[2]);
 			if (isbreak(x)) {
-				x = true;
+				x = trueval;
 				return(x);
 			}
 			if (isnext(x) || isexit(x))
@@ -879,7 +879,7 @@
 			tempfree(x);
 		}
 	}
-	return (true);
+	return (trueval);
 }
 
 obj jump(node **a,int n)
@@ -971,14 +971,14 @@
 	}
 	if (a[1]==nullstat) {
 		printf("%s", s);
-		return(true);
+		return(trueval);
 	}
 	redirprint(s, (intptr_t)a[1], a[2]);
-	return(false);
+	return(falseval);
 }
 
 /*ARGSUSED*/
-obj nullproc(node **a, int n) {return(true);}
+obj nullproc(node **a, int n) {return(trueval);}
 
 obj nodetoobj(node *a)
 {
--- a/shl/shl.c
+++ b/shl/shl.c
@@ -322,13 +322,16 @@
 	 */
 	struct passwd *pwd = getpwuid(myuid);
 	struct utmpx utx;
+	struct timeval tv;
 	char *id;
 
 	memset(&utx, 0, sizeof utx);
 	strncpy(utx.ut_line, l->l_line + 5, sizeof utx.ut_line);
 	strncpy(utx.ut_user, pwd->pw_name, sizeof utx.ut_user);
 	utx.ut_pid = l->l_pid;
-	gettimeofday(&utx.ut_tv, NULL);
+	gettimeofday(&tv, NULL);
+	utx.ut_tv.tv_sec = tv.tv_sec;
+	utx.ut_tv.tv_usec = tv.tv_usec;
 	if ((id = strrchr(l->l_line, '/')) != NULL)
 		strncpy(utx.ut_id, id, sizeof utx.ut_id);
 	switch (action) {