1) REALLY fix strcat crash (git restored wrong file in previous commit) 2) fopen: less labels ffs

src/string.asm

@@ -66,10 +66,12 @@ strcpy:
 ;	r8*	Backup for rdi (point to start of dest)
 ;	r9*	Backup for rsi
 ;	r10*	Backup for rdi (point to end of dest)
+;	r11*	Backup for strlen(dest)
 strcat:
 	mov	r8, rdi
 	mov	r9, rsi
 	call	strlen
+	mov	r11, rax
 	sub	rdx, rax
 	dec	rdi
 	mov	r10, rdi
@@ -78,13 +80,17 @@ strcat:
 	cmp	rax, rdx
 	jb	.copy
 	dec	rdx
+
 	.copy:
+	cmp	rdx, r11
+	jle	.quit
 	mov	rcx, rdx
 	mov	rsi, r9
 	mov	rdi, r10
 	cld
 	rep	movsb
 	mov	byte [rdi], EOS
+	.quit:
 	mov	rax, r8
 	ret