I changed the meta-arg parsers (C and Scheme) so that newline *always*

terminates an arg, even if it is an empty arg. Consistency. KISS.

Error-log

@@ -20,3 +20,6 @@ Tod Olson <ta-olson@uchicago.edu> complained about the I/O performance
     C support). Reported 11/95, improved 4/96.
     Things generally improved all over by improving the efficiency
     of optional argument handling (but especially I/O, I think).
+
+I changed the meta-arg parser (C, Scheme, and doc) so that newline
+    *always* terminates an arg -- empty or non-empty. KISS.

proc2.c

@@ -58,15 +58,16 @@
 ** - The only special chars are space, tab, newline, and \.
 ** - Every space char terminates an argument. 
 **   Multiple spaces therefore introduce empty-string arguments.
-** - A newline terminates the argument list, and will also terminate a
-**   non-empty argument (but a newline following a space does not introduce
-**   a final "" argument; it only terminates the argument list).
+** - A newline terminates an argument, and also terminates the argument list.
+**   This means that an empty line parses to the singleton list whose one
+**   element is the empty string: (""). The grammar doesn't admit the empty 
+**   list.
 ** - Tab is not allowed.
 **   This is to prevent you from being screwed by thinking you had several
 **   spaces where you really had a tab, and vice-versa.
 ** - The only other special character is \, the knock-down character. 
 **   \ escapes \, space, tab, and newline, turning off their special 
-**   functions. The ANSI C escape sequences, such as \n and \t are 
+**   functions. The ANSI C escape sequences (\b, \n, \r and \t) are 
 **   supported; these also produce argument-constituents -- \n doesn't act 
 **   like a terminating newline. \nnn for *exactly* three octal digits reads 
 **   as the char whose ASCII code is nnn. It is an error if \ is followed by 
@@ -190,14 +191,14 @@ char **process_meta_arg(char **av)
     argv = Malloc(char*, argv_len);
     if( !argv ) goto lose3;
 
-    while( EOF != (c=getc(script)) && '\n' != c ) {
+    do {
 	char *arg;
-	ungetc(c,script);
 	arg = read_arg(script);
 	if( !arg ) goto lose2;
 	Maybe_Grow_Vec(argv, argv_len, argv_i, char*, lose1);
 	argv[argv_i++] = arg;
 	}
+    while( EOF != (c=getc(script)) && '\n' != c );
 
     for(av_len=0; av[av_len]; av_len++);	/* Compute length of av. */
 
@@ -222,10 +223,9 @@ char **process_meta_arg(char **av)
     return NULL;
     }
 
-/* Read in one arg and it's terminating space.
-** If arg is terminated by a newline, leave the newline in
-** the stream so the outer loop can see it. Return a newly-allocated
-** string containing the arg; NULL if there's an error.
+/* Read in one arg, but not its terminating space or newline.
+** Return a newly-allocated string containing the arg; 
+** NULL if there's an error.
 */
 static char *read_arg(FILE *f)
 {
@@ -241,8 +241,7 @@ static char *read_arg(FILE *f)
     while(1) {
 	int c = getc(f);
 
-	if( c == EOF || c == ' ' ) break;
-	if( c == '\n' ) {ungetc(c, f); break;}
+	if( c == EOF || c == ' ' || c == '\n' ) {ungetc(c, f); break;}
 
 	/* Do knock-down processing. */
 	if( c == '\\' ) {

scsh/meta-arg.scm

@@ -65,22 +65,20 @@
 
 (define (read-secondary-args port)
   (let lp ((args '()))
-    (let ((c (peek-char port)))
+    (let* ((args (cons (read-secondary-arg port) args))
+	   (c (read-char port)))
       (if (or (eof-object? c) (char=? c #\newline))
 	  (reverse args)
-	  (lp (cons (read-secondary-arg port) args))))))
+	  (lp args)))))
 
-
-;;; Read in one secondary arg.
+;;; Read in one secondary arg, but not its delimiting space or newline.
 
 (define (read-secondary-arg port)
   (let lp ((chars '()))
     (let ((c (peek-char port)))
-      (cond ((or (eof-object? c) (char=? c #\newline))
-	     (apply string (reverse chars)))
-
-	    ((char=? c #\space)
-	     (read-char port)
+      (cond ((or (eof-object? c)
+		 (char=? c #\newline)
+		 (char=? c #\space))
 	     (apply string (reverse chars)))
 
 	    ((char=? c tab)