dir: Add support for posix_getdents()

This will be added to the next POSIX standard, and is already
implemented in musl.

Link: https://www.austingroupbugs.net/view.php?id=697
Link: https://git.musl-libc.org/cgit/musl/commit/?id=1b0d48517f816e98f19111df82f32bfc1608ecec

2 files changed, 22 insertions, 0 deletions

diff --git a/build/has/attribute-format-syslog.c b/build/has/attribute-format-syslog.c
new file mode 100644
index 0000000..ce988e5
--- /dev/null
+++ b/build/has/attribute-format-syslog.c
@@ -0,0 +1,13 @@
+// Copyright © Tavian Barnes <tavianator@tavianator.com>
+// SPDX-License-Identifier: 0BSD
+
+#include <stdio.h>
+
+__attribute__((format(syslog, 1, 2)))
+static int foo(const char *format, ...) {
+	return 0;
+}
+
+int main(void) {
+	return foo("%s: %m\n", "main()");
+}
diff --git a/build/has/posix-getdents.c b/build/has/posix-getdents.c
new file mode 100644
index 0000000..f74bbe5
--- /dev/null
+++ b/build/has/posix-getdents.c
@@ -0,0 +1,9 @@
+// Copyright © Tavian Barnes <tavianator@tavianator.com>
+// SPDX-License-Identifier: 0BSD
+
+#include <dirent.h>
+
+int main(void) {
+	char buf[1024];
+	return posix_getdents(3, (void *)buf, sizeof(buf), 0);
+}