From e8cb336ef5bc67dedc8e008f3ba3df7ac9555213 Mon Sep 17 00:00:00 2001
From: George Karypis <karypis@umn.edu>
Date: Sat, 30 May 2026 13:55:46 -0500
Subject: [PATCH] Use Windows system headers for POSIX read()/write()/getpid()
 (#45)

On Windows, read()/write() are declared in <io.h> and getpid() in <process.h>; modern Clang/clang-cl treat the missing declarations as hard errors (-Wimplicit-function-declaration), breaking src/io.c. Include those headers in the __MSC__ branch of gk_arch.h and drop the bundled win32/adapt.{c,h} shim (which only wrapped getpid() via <windows.h>) along with its target_sources entry.

Co-authored-by: Marijn Suijten <marijn@traverseresearch.nl>

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
---
 CMakeLists.txt        |  5 +----
 include/gk_arch.h     |  4 +++-
 include/win32/adapt.h | 14 --------------
 src/win32/adapt.c     | 11 -----------
 4 files changed, 4 insertions(+), 30 deletions(-)
 delete mode 100644 include/win32/adapt.h
 delete mode 100644 src/win32/adapt.c

diff --git a/CMakeLists.txt b/CMakeLists.txt
index e87970a..cc386c1 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -78,10 +78,7 @@ target_sources(${PROJECT_NAME}
           include/gk_mkpqueue2.h include/gk_mkrandom.h include/gk_mksort.h 
           include/gk_mkutils.h include/gk_proto.h include/gk_struct.h
           include/gk_types.h include/gkregex.h include/gk_ms_inttypes.h 
-          include/gk_ms_stat.h include/gk_ms_stdint.h
-          # the following are shims for win32 systems
-          $<$<PLATFORM_ID:Windows>:src/win32/adapt.c
-                                   include/win32/adapt.h>)
+          include/gk_ms_stat.h include/gk_ms_stdint.h)
 
 target_compile_definitions(${PROJECT_NAME}
   PUBLIC $<$<PLATFORM_ID:Linux>:LINUX>
diff --git a/include/gk_arch.h b/include/gk_arch.h
index 0f04491..b5b290b 100644
--- a/include/gk_arch.h
+++ b/include/gk_arch.h
@@ -41,7 +41,9 @@
     #include "gk_ms_inttypes.h"
   #endif
   #include "gk_ms_stat.h"
-  #include "win32/adapt.h"
+  #include <io.h>
+  #include <process.h>
+  typedef int pid_t;
 #else
 #ifndef SUNOS
   #include <stdint.h>
diff --git a/include/win32/adapt.h b/include/win32/adapt.h
deleted file mode 100644
index 35e60ed..0000000
--- a/include/win32/adapt.h
+++ /dev/null
@@ -1,14 +0,0 @@
-/*
-\file  win32/adapt.h
-\brief Declaration of Win32 adaptation of POSIX functions and types
-*/
-#ifndef _WIN32_ADAPT_H_
-#define _WIN32_ADAPT_H_
-
-#include <windows.h>
-
-typedef DWORD pid_t;
-
-pid_t getpid(void);
-
-#endif  /* _WIN32_ADAPT_H_ */
diff --git a/src/win32/adapt.c b/src/win32/adapt.c
deleted file mode 100644
index 546857c..0000000
--- a/src/win32/adapt.c
+++ /dev/null
@@ -1,11 +0,0 @@
-/*
-\file  win32/adapt.c
-\brief Implementation of Win32 adaptation of libc functions
-*/
-
-#include "adapt.h"
-
-pid_t getpid(void)
-{
-  return GetCurrentProcessId();
-}