diff --git a/include/boost/process/v2/posix/default_launcher.hpp b/include/boost/process/v2/posix/default_launcher.hpp
index 9cfec4b2a..09f8ce428 100644
--- a/include/boost/process/v2/posix/default_launcher.hpp
+++ b/include/boost/process/v2/posix/default_launcher.hpp
@@ -29,7 +29,7 @@
 #include <unistd.h>
 
 
-#if defined(__NetBSD__) || defined(__FreeBSD__) || defined(__APPLE__) || defined(__MACH__)
+#if defined(__APPLE__) || defined(__MACH__) || defined(__FreeBSD__) || defined(__NetBSD__) || defined(__OpenBSD__)
 extern "C" { extern char **environ; }
 #endif
 
diff --git a/src/ext/cmd.cpp b/src/ext/cmd.cpp
index d74a06ef4..58e16db5e 100644
--- a/src/ext/cmd.cpp
+++ b/src/ext/cmd.cpp
@@ -343,7 +343,7 @@ shell cmd(boost::process::v2::pid_type pid, boost::system::error_code & ec)
     };
 
     std::unique_ptr<kvm_t, closer> kd{kvm_openfiles(nullptr, nullptr, nullptr, KVM_NO_FILES, nullptr)};
-    if (!kd) {BOOST_PROCESS_V2_ASSIGN_LAST_ERROR(ec) return vec;}
+    if (!kd.get()) {BOOST_PROCESS_V2_ASSIGN_LAST_ERROR(ec) return {};}
     if ((proc_info = kvm_getprocs(kd.get(), KERN_PROC_PID, pid, sizeof(struct kinfo_proc), &cntp))) 
     {
         char **cmd = kvm_getargv(kd.get(), proc_info, 0);
@@ -354,7 +354,7 @@ shell cmd(boost::process::v2::pid_type pid, boost::system::error_code & ec)
     }
     else
         BOOST_PROCESS_V2_ASSIGN_LAST_ERROR(ec)
-    kvm_close(kd);
+    kvm_close(kd.get());
     return {};
 }
     
diff --git a/src/pid.cpp b/src/pid.cpp
index f32df9ecc..574a38cf7 100644
--- a/src/pid.cpp
+++ b/src/pid.cpp
@@ -551,9 +551,9 @@ std::vector<pid_type> all_pids(boost::system::error_code & ec)
         vec.reserve(cntp);
         for (int i = cntp - 1; i >= 0; i--)
         {
-            if (proc_info[i].kp_pid >= 0) 
+            if (proc_info[i].p_pid >= 0) 
             {
-                vec.push_back(proc_info[i].kp_pid);
+                vec.push_back(proc_info[i].p_pid);
             }
         }
     }
diff --git a/src/posix/close_handles.cpp b/src/posix/close_handles.cpp
index 39d63e6dd..67b6381d4 100644
--- a/src/posix/close_handles.cpp
+++ b/src/posix/close_handles.cpp
@@ -17,10 +17,9 @@
 // linux has close_range since 5.19
 
 
-#if defined(__NetBSD__) || defined(__FreeBSD__) || defined(__OpenBSD__)
+#if defined(__FreeBSD__)
 
 // https://www.freebsd.org/cgi/man.cgi?query=close_range&apropos=0&sektion=0&manpath=FreeBSD+13.1-RELEASE+and+Ports&arch=default&format=html
-// https://man.netbsd.org/closefrom.3
 // __FreeBSD__
 // 
 // gives us
diff --git a/src/shell.cpp b/src/shell.cpp
index 0fffc501a..a03d30096 100644
--- a/src/shell.cpp
+++ b/src/shell.cpp
@@ -19,7 +19,7 @@
 #if defined(BOOST_PROCESS_V2_WINDOWS)
 #include <windows.h>
 #include <shellapi.h>
-#else
+#elif defined(__OpenBSD__)
 #include <wordexp.h>
 #endif
 
@@ -30,7 +30,7 @@ BOOST_PROCESS_V2_DECL const error_category& get_shell_category()
 {
     return system_category();
 }
-#else
+#elif defined(__OpenBSD__)
 
 struct shell_category_t final : public error_category
 {
@@ -92,7 +92,7 @@ auto shell::args() const-> args_type
     return input_.c_str();
 }
 
-#else
+#elif defined(__OpenBSD__)
 
 void shell::parse_()
 {