From 9815b8b06d71917e350221f77956cdd2a8d3ef97 Mon Sep 17 00:00:00 2001
From: Matheus <matheusuky@gmail.com>
Date: Mon, 24 Oct 2022 15:35:33 -0300
Subject: [PATCH] fcntl: properly handle F_SETFL now

---
 src/sys/syscalls/fcntl.c | 13 ++++++++++++-
 1 file changed, 12 insertions(+), 1 deletion(-)

diff --git a/src/sys/syscalls/fcntl.c b/src/sys/syscalls/fcntl.c
index fe2bc991..d09ffd86 100644
--- a/src/sys/syscalls/fcntl.c
+++ b/src/sys/syscalls/fcntl.c
@@ -36,7 +36,18 @@ syscallret syscall_fcntl(int ifd, int cmd, uint64_t arg){
 		case F_GETFL:
 			retv.ret = fd->flags;
 			break;
-		case F_SETFL: // no useful status flags implemented
+		case F_SETFL:
+			// mask away things that shouldn't be changed
+			arg &= ~(O_RDONLY | O_WRONLY | O_RDWR | O_CREAT | O_EXCL | O_NOCTTY | O_TRUNC);
+			
+			// and mask away from the flags the things that will be set
+			
+			fd->flags &= ~(O_APPEND | O_ASYNC | O_NOATIME | O_NONBLOCK);
+
+			// finally set the flags
+
+			fd->flags |= arg;
+
 			retv.ret = 0;
 			break;
 		default: