perf: quicker check/removal of escaped newlines for Windows

src/common/fgetline.c

@@ -1,5 +1,5 @@
 #ifndef lint
-static const char	RCSid[] = "$Id: fgetline.c,v 2.10 2020/07/29 18:19:31 greg Exp $";
+static const char	RCSid[] = "$Id: fgetline.c,v 2.11 2020/07/30 17:25:01 greg Exp $";
 #endif
 /*
  * fgetline.c - read line with escaped newlines.
@@ -35,9 +35,10 @@ fgetline(		/* read in line with escapes, elide final newline */
 		return(NULL);
 	*cp = '\0';
 #if defined(_WIN32) || defined(_WIN64)
-						/* remove escaped newlines */
-	for (cp = s; (cp = strchr(cp, '\\')) != NULL && cp[1] == '\n'; )
-		memmove(cp, cp+2, strlen(cp+2)+1);
+	for (cp = s; *cp; cp++)			/* remove escaped newlines */
+		if (cp[0] == '\\' && cp[1] == '\n') {
+			*cp++ = ' '; *cp = ' ';
+		}
 #endif
 	return(s);
 }