From 7127931f3be3c4fe201b71c8526e96be560f3107 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Tom=C3=A1s=20Andr=C3=B3il?= <tomasandroil@gmail.com>
Date: Mon, 28 Apr 2025 11:35:03 +0200
Subject: [PATCH] fix(subprocess): check and handle fcntl(F_GETFD) failure

Add missing error check for fcntl(fd, F_GETFD, 0) in set_clo_on_exec.
Raise OSError on failure to align with existing FD_SETFD behavior.
This improves robustness in subprocess setup and error visibility.
---
 subprocess.hpp | 8 ++++++--
 1 file changed, 6 insertions(+), 2 deletions(-)

diff --git a/subprocess.hpp b/subprocess.hpp
index 073f075..1b35574 100755
--- a/subprocess.hpp
+++ b/subprocess.hpp
@@ -471,10 +471,14 @@ namespace util
   void set_clo_on_exec(int fd, bool set = true)
   {
     int flags = fcntl(fd, F_GETFD, 0);
+    if (flags == -1) {
+        throw OSError("fcntl F_GETFD failed", errno);
+    }
     if (set) flags |= FD_CLOEXEC;
     else flags &= ~FD_CLOEXEC;
-    //TODO: should check for errors
-    fcntl(fd, F_SETFD, flags);
+    if (fcntl(fd, F_SETFD, flags) == -1) {
+        throw OSError("fcntl F_SETFD failed", errno);
+    }
   }