diff --git a/src/console.asm b/src/console.asm
index ab6534b..4fecfa9 100644
--- a/src/console.asm
+++ b/src/console.asm
@@ -194,10 +194,12 @@ __INTERNAL_fmt:
 	jmp	.insertString
 	%endmacro
 
-	%macro check_formatted_len 2 ;check_format_len [return_label] [offset]
+	%macro check_formatted_len 2 ;check_format_len [return_label] [length offset]
 	test	rbx, rbx
 	jz	%%checkBufferLen
-	cmp	r11, rbx
+	mov	rax, r11
+	add	rax, %2
+	cmp	rax, rbx
 	jae	.wrapup
 	jmp	.flushReturn_%1
 	%%checkBufferLen:
@@ -260,6 +262,7 @@ __INTERNAL_fmt:
 		cmp	byte [rdi], EOS
 		je	.wrapup
 			check_formatted_len 0,1
+		;.flushReturn_0:
 		cmp	byte [rdi], '\'
 		je	.asciiReplacement
 		cmp	byte [rdi], '%'
@@ -286,6 +289,7 @@ __INTERNAL_fmt:
 		jmp	.invalidReplacement
 		.replaceAscii:
 			check_formatted_len 1, 1
+		;.flushReturn_1:
 			write_format_data byte,r10,r8b
 		add	rdi, 2
 		inc	r10
@@ -443,18 +447,43 @@ __INTERNAL_fmt:
 		.insertString:
 			test	rsi, rsi
 			jnz	.doInsertString
-				check_formatted_len 2, 7
+				check_formatted_len 2, 1
+			;.flushReturn_2:
 				write_format_data byte,r10,'('
-				write_format_data qword,r10+1,'null'
-				write_format_data byte,r10+5,')'
-			add	r10, 6
-			add	r11, 6
+			inc	r10
+			inc	r11
+				check_formatted_len 21, 1
+			;.flushReturn_21:
+				write_format_data byte,r10,'n'
+			inc	r10
+			inc	r11
+				check_formatted_len 22, 1
+			;.flushReturn_22:
+				write_format_data byte,r10,'u'
+			inc	r10
+			inc	r11
+				check_formatted_len 23, 1
+			;.flushReturn_23:
+				write_format_data byte,r10,'l'
+			inc	r10
+			inc	r11
+				check_formatted_len 24, 1
+			;.flushReturn_24:
+				write_format_data byte,r10,'l'
+			inc	r10
+			inc	r11
+				check_formatted_len 25, 1
+			;.flushReturn_25:
+				write_format_data byte,r10,')'
+			inc	r10
+			inc	r11
 			jmp	.endInsertString
 
 			.doInsertString:
 			cmp	byte [rsi], EOS
 			je	.endInsertString
 				check_formatted_len 3, 1
+			;.flushReturn_3:
 			mov	r8b, byte [rsi]
 				write_format_data byte,r10,r8b
 			inc	rsi
@@ -512,13 +541,23 @@ __INTERNAL_fmt:
 	xor	r10, r10
 	.flush_ret:
 	cmp	r9b, 0
-	je	.flushReturn_0
+	je	.flushReturn_0	;.process
 	cmp	r9b, 1
-	je	.flushReturn_1
+	je	.flushReturn_1	;.replaceAscii
 	cmp	r9b, 2
-	je	.flushReturn_2
+	je	.flushReturn_2	;.insertString "(null)
+	cmp	r9b, 21
+	je	.flushReturn_21	;...
+	cmp	r9b, 22
+	je	.flushReturn_22	;...
+	cmp	r9b, 23
+	je	.flushReturn_23	;...
+	cmp	r9b, 24
+	je	.flushReturn_24	;...
+	cmp	r9b, 25
+	je	.flushReturn_25	;...
 	cmp	r9b, 3
-	je	.flushReturn_3
+	je	.flushReturn_3	;.doInsertString
 
 	.wrapup:
 	test	rbx, rbx
diff --git a/src/tests.asm b/src/tests.asm
index 25425a2..1326a8c 100644
--- a/src/tests.asm
+++ b/src/tests.asm
@@ -422,11 +422,7 @@ section .rodata
 	addTest(fgetmod2, "fgetmod(statbuff2)")
 	fgetmodStr	db	"\t- File permissions of file '%s': %04o\n",EOS
 
-	fmt_str		db	"%s",EOS
-
 section .bss
-	fmt_out		resb	5
-	fmt_over	resb	64
 	inputBuffer_4	resb	4
 	inputBuffer_32	resb	32
 	strBuff1	resb	64
@@ -1665,16 +1661,6 @@ _start:
 	sub	rcx, r14
 	call	printf
 
-	lea	rdi, [rel fmt_out]
-	mov	rsi, 5
-	lea	rdx, [rel fmt_str]
-	xor	rcx, rcx
-	call	format
-	lea	rdi, [rel fmt_out]
-	call	puts
-	lea	rdi, [rel fmt_over]
-	call	puts
-
 ;--- exit()
 	xor	rdi, rdi
 	call	exit