syscalls: isatty

kernel-src/sys/syscalls/isatty.c

@@ -0,0 +1,25 @@
+#include <kernel/syscalls.h>
+#include <kernel/vfs.h>
+#include <kernel/file.h>
+
+syscallret_t syscall_isatty(context_t *context, int fd) {
+	syscallret_t ret = {
+		.ret = -1
+	};
+
+	file_t *file = fd_get(fd);
+	if (file == NULL) {
+		ret.errno = EBADF;
+		return ret;
+	}
+
+	// mlibc expects isatty to return 1 if a terminal and 0 if not.
+	int e = VOP_ISATTY(file->vnode);
+
+	ret.errno = e;
+	ret.ret = e ? 0 : 1;
+
+	fd_release(file);
+
+	return ret;
+}