Kernel+LibC: Switch isatty() to use a fcntl()

We would want it to work with only stdio pledged.

2 files changed, 2 insertions, 2 deletions

diff --git a/Libraries/LibC/fcntl.h b/Libraries/LibC/fcntl.h
index d56dae85f5..1aa6e6cd09 100644
--- a/Libraries/LibC/fcntl.h
+++ b/Libraries/LibC/fcntl.h
@@ -36,6 +36,7 @@ __BEGIN_DECLS
 #define F_SETFD 2
 #define F_GETFL 3
 #define F_SETFL 4
+#define F_ISTTY 5
 
 #define FD_CLOEXEC 1
 
diff --git a/Libraries/LibC/unistd.cpp b/Libraries/LibC/unistd.cpp
index 652eaabe43..ec01ad1be4 100644
--- a/Libraries/LibC/unistd.cpp
+++ b/Libraries/LibC/unistd.cpp
@@ -413,8 +413,7 @@ int rmdir(const char* pathname)
 
 int isatty(int fd)
 {
-    struct termios dummy;
-    return tcgetattr(fd, &dummy) == 0;
+    return fcntl(fd, F_ISTTY);
 }
 
 int dup(int old_fd)