[Python] How to Wrap SteamAPI_InitFlat in Python without using SteamworksPy

I am developing my first game for steam, and I am trying to get the basic steam flat file to work in python. The library that did this seems to be dead (steamworkspy), and is not trivial to set up in the first place.

I have written code that wraps the redistributable dlls in python as shown below.

import os
os.environ["SteamAppId"] = "480"
os.environ["SteamDebug"] = "1"

import ctypes

import platform
import sys
import time

def check_steam_restart(dll_path, app_id):
steam = ctypes.windll.LoadLibrary(dll_path)
func = steam.SteamAPI_RestartAppIfNecessary
func.argtypes = [ctypes.c_uint32]
func.restype = ctypes.c_bool

result = func(ctypes.c_uint32(app_id))
print(f"SteamAPI_RestartAppIfNecessary returned: {result}")
if result:
print("Steam needs to relaunch the app through Steam — exiting...")
sys.exit(0)

class Steam:
def __init__(self):
self._dll = self._load_library()
self._initialize_functions()

def _check_symbol(self, symbol_name):
if not hasattr(self._dll, symbol_name):
raise Exception(f"Function '{symbol_name}' not found in Steamworks library.")

def _load_library(self):
"""Load the correct platform-specific Steamworks DLL."""
redistributable_bin_path = {
'Windows': {
'64bit': r'steamworks_sdk_162\sdk\redistributable_bin\win64\steam_api64.dll',
'32bit': r'steamworks_sdk_162\sdk\redistributable_bin\steam_api.dll'
},
'Linux': {
'64bit': r'steamworks_sdk_162/sdk/redistributable_bin/linux64/libsteam_api.so',
'32bit': r'steamworks_sdk_162/sdk/redistributable_bin/linux32/libsteam_api.so'
}
}

system = platform.system()
architecture = platform.architecture()[0]

if system not in redistributable_bin_path or architecture not in redistributable_bin_path[system]:
raise OSError(f'Unsupported platform or architecture: {system} {architecture}')

library_path = os.path.join(
os.path.dirname(os.path.abspath(__file__)),
redistributable_bin_path[system][architecture]
)

if not os.path.exists(library_path):
raise FileNotFoundError(f"Steamworks library not found at {library_path}")

print(f"Steamworks library located: {library_path}")

if system == 'Windows':
return ctypes.windll.LoadLibrary(library_path)
else:
return ctypes.CDLL(library_path)

def _initialize_functions(self):
# Step 2: Initialize Steam via InitFlat
if hasattr(self._dll, "SteamAPI_InitFlat"):
print("Using SteamAPI_InitFlat")
self._dll.SteamAPI_InitFlat.argtypes = []
self._dll.SteamAPI_InitFlat.restype = ctypes.c_bool
else:
raise Exception("SteamAPI_InitFlat not found in DLL")

# Step 3: Register Shutdown (for __exit__)
if hasattr(self._dll, "SteamAPI_Shutdown"):
self._dll.SteamAPI_Shutdown.argtypes = []
self._dll.SteamAPI_Shutdown.restype = None
else:
raise Exception("SteamAPI_Shutdown not found in DLL")

def __enter__(self):
# Optional: Check if Steam is running
if hasattr(self._dll, "SteamAPI_IsSteamRunning"):
self._dll.SteamAPI_IsSteamRunning.restype = ctypes.c_bool
running = self._dll.SteamAPI_IsSteamRunning()
print(f"Steam running: {running}")

print("Initializing Steam API via Flat...")
if not self._dll.SteamAPI_InitFlat():
raise Exception("SteamAPI_InitFlat failed")
print("Steam API initialized successfully.")
return self

def __exit__(self, exc_type, exc_val, exc_tb):
print("Shutting down Steam API...")
self._dll.SteamAPI_Shutdown()



if __name__ == "__main__":
try:
dll_path = os.path.join(
os.path.dirname(os.path.abspath(__file__)),
r"steamworks_sdk_162\sdk\redistributable_bin\win64\steam_api64.dll"
)

app_id = int(os.environ["SteamAppId"])
print(f"Using App ID: {app_id}")
check_steam_restart(dll_path, app_id)
with Steam() as steam:
print("Steam API initialized successfully.")

# Debugging HSteamPipe and HSteamUser
# mod_manager = ModManager(steam._dll)
# print(f"HSteamPipe: {mod_manager._steam_pipe}")
# print(f"HSteamUser: {mod_manager._steam_user}")

# # Test ISteamUGC interface retrieval
# ugc_interface = mod_manager._ugc_interface
# print(f"ISteamUGC interface retrieved: {ugc_interface}")

except Exception as e:
print(f"Error: {e}")


However, this returns a very unhelpful error, usually something I see in memory management.

(venv) D:\97cweb\Documents\Projects\SimAntics\py-lua\simantics_SteamworksWrapper\simantics_SteamworksWrapper>python steam.py
Using App ID: 480
SteamAPI_RestartAppIfNecessary returned: False
Steamworks library located: D:\97cweb\Documents\Projects\SimAntics\py-lua\simantics_SteamworksWrapper\simantics_SteamworksWrapper\steamworks_sdk_162\sdk\redistributable_bin\win64\steam_api64.dll
Using SteamAPI_InitFlat
Steam running: True
Initializing Steam API via Flat...
Setting breakpad minidump AppID = 480
SteamInternal_SetMinidumpSteamID: Caching Steam ID: 76561198283721268 [API loaded no]
Error: exception: access violation writing 0x0000000000000001


Any help getting this to work is greatly appreciated. I did try google and the robot to get this to work as well, so just google it is not the answer.

Continue reading...