diff --git a/src/window.c b/src/window.c
index cba9785..b9617f0 100644
--- a/src/window.c
+++ b/src/window.c
@@ -836,8 +836,7 @@
 							frp = frp->fr_parent)
 	    {
 		if (frp->fr_layout == FR_ROW)
-		    for (frp2 = frp->fr_child; frp2 != NULL;
-							frp2 = frp2->fr_next)
+		    FOR_ALL_FRAMES(frp2, frp->fr_child)
 			if (frp2 != prevfrp)
 			    minwidth += frame_minwidth(frp2, NOWIN);
 		prevfrp = frp;
@@ -920,8 +919,7 @@
 							frp = frp->fr_parent)
 	    {
 		if (frp->fr_layout == FR_COL)
-		    for (frp2 = frp->fr_child; frp2 != NULL;
-							frp2 = frp2->fr_next)
+		    FOR_ALL_FRAMES(frp2, frp->fr_child)
 			if (frp2 != prevfrp)
 			    minheight += frame_minheight(frp2, NOWIN);
 		prevfrp = frp;
@@ -1078,7 +1076,7 @@
 	if (frp->fr_win != NULL)
 	    oldwin->w_frame = frp;
 	else
-	    for (frp = frp->fr_child; frp != NULL; frp = frp->fr_next)
+	    FOR_ALL_FRAMES(frp, frp->fr_child)
 		frp->fr_parent = curfrp;
     }
 
@@ -1605,8 +1603,7 @@
 #endif
 
     /* Check if all frames in this row/col have one window. */
-    for (frp = curwin->w_frame->fr_parent->fr_child; frp != NULL;
-							   frp = frp->fr_next)
+    FOR_ALL_FRAMES(frp, curwin->w_frame->fr_parent->fr_child)
 	if (frp->fr_win == NULL)
 	{
 	    EMSG(_("E443: Cannot rotate when another window is split"));
@@ -1856,7 +1853,7 @@
 	    else
 	    {
 		next_curwin_size = -1;
-		for (fr = topfr->fr_child; fr != NULL; fr = fr->fr_next)
+		FOR_ALL_FRAMES(fr, topfr->fr_child)
 		{
 		    /* If 'winfixwidth' set keep the window width if
 		     * possible.
@@ -1909,7 +1906,7 @@
 		--totwincount;		/* don't count curwin */
 	}
 
-	for (fr = topfr->fr_child; fr != NULL; fr = fr->fr_next)
+	FOR_ALL_FRAMES(fr, topfr->fr_child)
 	{
 	    wincount = 1;
 	    if (fr->fr_next == NULL)
@@ -1997,7 +1994,7 @@
 	    else
 	    {
 		next_curwin_size = -1;
-		for (fr = topfr->fr_child; fr != NULL; fr = fr->fr_next)
+		FOR_ALL_FRAMES(fr, topfr->fr_child)
 		{
 		    /* If 'winfixheight' set keep the window height if
 		     * possible.
@@ -2050,7 +2047,7 @@
 		--totwincount;		/* don't count curwin */
 	}
 
-	for (fr = topfr->fr_child; fr != NULL; fr = fr->fr_next)
+	FOR_ALL_FRAMES(fr, topfr->fr_child)
 	{
 	    wincount = 1;
 	    if (fr->fr_next == NULL)
@@ -2751,7 +2748,7 @@
 	 * and remove it. */
 	frp2->fr_parent->fr_layout = frp2->fr_layout;
 	frp2->fr_parent->fr_child = frp2->fr_child;
-	for (frp = frp2->fr_child; frp != NULL; frp = frp->fr_next)
+	FOR_ALL_FRAMES(frp, frp2->fr_child)
 	    frp->fr_parent = frp2->fr_parent;
 	frp2->fr_parent->fr_win = frp2->fr_win;
 	if (frp2->fr_win != NULL)
@@ -2883,7 +2880,7 @@
     if (frp->fr_layout == FR_LEAF)
 	return frp->fr_win == wp;
 
-    for (p = frp->fr_child; p != NULL; p = p->fr_next)
+    FOR_ALL_FRAMES(p, frp->fr_child)
 	if (frame_has_win(p, wp))
 	    return TRUE;
     return FALSE;
@@ -2917,7 +2914,7 @@
 	do
 	{
 	    /* All frames in this row get the same new height. */
-	    for (frp = topfrp->fr_child; frp != NULL; frp = frp->fr_next)
+	    FOR_ALL_FRAMES(frp, topfrp->fr_child)
 	    {
 		frame_new_height(frp, height, topfirst, wfh);
 		if (frp->fr_height > height)
@@ -3014,7 +3011,7 @@
     {
 	/* The frame is fixed height if one of the frames in the row is fixed
 	 * height. */
-	for (frp = frp->fr_child; frp != NULL; frp = frp->fr_next)
+	FOR_ALL_FRAMES(frp, frp->fr_child)
 	    if (frame_fixed_height(frp))
 		return TRUE;
 	return FALSE;
@@ -3022,7 +3019,7 @@
 
     /* frp->fr_layout == FR_COL: The frame is fixed height if all of the
      * frames in the row are fixed height. */
-    for (frp = frp->fr_child; frp != NULL; frp = frp->fr_next)
+    FOR_ALL_FRAMES(frp, frp->fr_child)
 	if (!frame_fixed_height(frp))
 	    return FALSE;
     return TRUE;
@@ -3043,7 +3040,7 @@
     {
 	/* The frame is fixed width if one of the frames in the row is fixed
 	 * width. */
-	for (frp = frp->fr_child; frp != NULL; frp = frp->fr_next)
+	FOR_ALL_FRAMES(frp, frp->fr_child)
 	    if (frame_fixed_width(frp))
 		return TRUE;
 	return FALSE;
@@ -3051,7 +3048,7 @@
 
     /* frp->fr_layout == FR_ROW: The frame is fixed width if all of the
      * frames in the row are fixed width. */
-    for (frp = frp->fr_child; frp != NULL; frp = frp->fr_next)
+    FOR_ALL_FRAMES(frp, frp->fr_child)
 	if (!frame_fixed_width(frp))
 	    return FALSE;
     return TRUE;
@@ -3079,7 +3076,7 @@
     else if (frp->fr_layout == FR_ROW)
     {
 	/* Handle all the frames in the row. */
-	for (frp = frp->fr_child; frp != NULL; frp = frp->fr_next)
+	FOR_ALL_FRAMES(frp, frp->fr_child)
 	    frame_add_statusline(frp);
     }
     else /* frp->fr_layout == FR_COL */
@@ -3125,7 +3122,7 @@
 	do
 	{
 	    /* All frames in this column get the same new width. */
-	    for (frp = topfrp->fr_child; frp != NULL; frp = frp->fr_next)
+	    FOR_ALL_FRAMES(frp, topfrp->fr_child)
 	    {
 		frame_new_width(frp, width, leftfirst, wfw);
 		if (frp->fr_width > width)
@@ -3228,7 +3225,7 @@
     else if (frp->fr_layout == FR_COL)
     {
 	/* Handle all the frames in the column. */
-	for (frp = frp->fr_child; frp != NULL; frp = frp->fr_next)
+	FOR_ALL_FRAMES(frp, frp->fr_child)
 	    frame_add_vsep(frp);
     }
     else /* frp->fr_layout == FR_ROW */
@@ -3295,7 +3292,7 @@
     {
 	/* get the minimal height from each frame in this row */
 	m = 0;
-	for (frp = topfrp->fr_child; frp != NULL; frp = frp->fr_next)
+	FOR_ALL_FRAMES(frp, topfrp->fr_child)
 	{
 	    n = frame_minheight(frp, next_curwin);
 	    if (n > m)
@@ -3306,7 +3303,7 @@
     {
 	/* Add up the minimal heights for all frames in this column. */
 	m = 0;
-	for (frp = topfrp->fr_child; frp != NULL; frp = frp->fr_next)
+	FOR_ALL_FRAMES(frp, topfrp->fr_child)
 	    m += frame_minheight(frp, next_curwin);
     }
 
@@ -3344,7 +3341,7 @@
     {
 	/* get the minimal width from each frame in this column */
 	m = 0;
-	for (frp = topfrp->fr_child; frp != NULL; frp = frp->fr_next)
+	FOR_ALL_FRAMES(frp, topfrp->fr_child)
 	{
 	    n = frame_minwidth(frp, next_curwin);
 	    if (n > m)
@@ -3355,7 +3352,7 @@
     {
 	/* Add up the minimal widths for all frames in this row. */
 	m = 0;
-	for (frp = topfrp->fr_child; frp != NULL; frp = frp->fr_next)
+	FOR_ALL_FRAMES(frp, topfrp->fr_child)
 	    m += frame_minwidth(frp, next_curwin);
     }
 
@@ -5023,7 +5020,7 @@
     {
 	startrow = *row;
 	startcol = *col;
-	for (frp = topfrp->fr_child; frp != NULL; frp = frp->fr_next)
+	FOR_ALL_FRAMES(frp, topfrp->fr_child)
 	{
 	    if (topfrp->fr_layout == FR_ROW)
 		*row = startrow;	/* all frames are at the same row */
@@ -5143,8 +5140,7 @@
 	{
 	    room = 0;
 	    room_reserved = 0;
-	    for (frp = curfrp->fr_parent->fr_child; frp != NULL;
-							   frp = frp->fr_next)
+	    FOR_ALL_FRAMES(frp, curfrp->fr_parent->fr_child)
 	    {
 		if (frp != curfrp
 			&& frp->fr_win != NULL
@@ -5337,8 +5333,7 @@
 	{
 	    room = 0;
 	    room_reserved = 0;
-	    for (frp = curfrp->fr_parent->fr_child; frp != NULL;
-							   frp = frp->fr_next)
+	    FOR_ALL_FRAMES(frp, curfrp->fr_parent->fr_child)
 	    {
 		if (frp != curfrp
 			&& frp->fr_win != NULL
@@ -5562,7 +5557,7 @@
 	if (room < 0)
 	    room = 0;
 	/* sum up the room of frames below of the current one */
-	for (fr = curfr->fr_next; fr != NULL; fr = fr->fr_next)
+	FOR_ALL_FRAMES(fr, curfr->fr_next)
 	    room += fr->fr_height - frame_minheight(fr, NULL);
 	fr = curfr;			/* put fr at window that grows */
     }
@@ -5676,7 +5671,7 @@
 	left = FALSE;
 	/* sum up the room of frames right of the current one */
 	room = 0;
-	for (fr = curfr->fr_next; fr != NULL; fr = fr->fr_next)
+	FOR_ALL_FRAMES(fr, curfr->fr_next)
 	    room += fr->fr_width - frame_minwidth(fr, NULL);
 	fr = curfr;			/* put fr at window that grows */
     }
@@ -6073,7 +6068,7 @@
     else if (fr->fr_layout == FR_ROW)
     {
 	/* vertically split windows, set status line for each one */
-	for (fp = fr->fr_child; fp != NULL; fp = fp->fr_next)
+	FOR_ALL_FRAMES(fp, fr->fr_child)
 	    last_status_rec(fp, statusline);
     }
     else
@@ -6751,7 +6746,7 @@
 	return TRUE;
 
     if (topframe->fr_layout == FR_COL)
-	for (fr = topframe->fr_child; fr != NULL; fr = fr->fr_next)
+	FOR_ALL_FRAMES(fr, topframe->fr_child)
 	    if (fr->fr_layout == FR_ROW)
 		return TRUE;
 
@@ -7097,7 +7092,7 @@
 	return FALSE;
 
     if (topfrp->fr_layout == FR_ROW)
-	for (frp = topfrp->fr_child; frp != NULL; frp = frp->fr_next)
+	FOR_ALL_FRAMES(frp, topfrp->fr_child)
 	    if (frp->fr_height != height)
 		return FALSE;
 
@@ -7116,7 +7111,7 @@
 	return FALSE;
 
     if (topfrp->fr_layout == FR_COL)
-	for (frp = topfrp->fr_child; frp != NULL; frp = frp->fr_next)
+	FOR_ALL_FRAMES(frp, topfrp->fr_child)
 	    if (frp->fr_width != width)
 		return FALSE;