Exit Codes Windows [cracked] 〈100% Popular〉

> net helpmsg 2 The system cannot find the file specified. If the program is well-known (e.g., robocopy , xcopy ), consult its documentation—they reuse Win32 error codes with different meanings.

| Category | Range (Hex) | Example | Meaning | |----------|-------------|---------|---------| | | 0x00000000–0x0000FFFF | 1 , 2 | Custom error (e.g., invalid input) | | Win32 Error Codes | 0x00000000–0x0000FFFF (overlap!) | ERROR_FILE_NOT_FOUND (2) | System API failure | | NTSTATUS Codes | 0xC0000000–0xFFFFFFFF | 0xC0000005 | Access violation (structured exception) | | HRESULT | 0x80070000–0x8007FFFF | 0x80070002 | COM error, wraps Win32 error 2 |

This overlap is a trap: an exit code of 2 could mean "invalid parameter" (application-defined), or it could mean ERROR_FILE_NOT_FOUND from a failed CreateFile . Without the program's documentation, you cannot disambiguate. Three common scenarios produce exit codes that are technically correct but semantically useless: exit codes windows

In cmd.exe , the exit code of a batch file is the exit code of the last command executed . A batch file that copies a file and then echoes a message will return 0 even if the copy failed, because echo always succeeds. This forces developers to use exit /b %errorlevel% explicitly.

Crucially, the exit code is the return value of main() in the C runtime sense. The CRT wraps main() , captures its return value, and passes it to ExitProcess() . If you never call ExitProcess explicitly, the CRT does it for you. > net helpmsg 2 The system cannot find the file specified

PowerShell-native commands return rich objects, not exit codes. When you run an external .exe , PowerShell captures its exit code in $LASTEXITCODE , but the PowerShell process's own exit code is set only by exit $n . A script that runs non-existent.exe will see $LASTEXITCODE = 0xC0000135 (STATUS_DLL_NOT_FOUND), but the PowerShell process itself exits with 0 unless you explicitly forward it. 4. The Debugger's Compass: Interpreting Exit Codes as Clues For a systems engineer, an unexpected exit code is a compressed diagnostic. Here’s how to decompress it:

This layering leads to a key insight: . The default for a thread is STATUS_THREAD_TERMINATED (0x00000100); for a process, it is STATUS_PENDING (0x00000103) until termination, then the final code. 2. The Semantic Wasteland: What Does Non-Zero Mean? Unlike Unix, where exit codes are small (0–255) and often mapped to sysexits.h conventions, Windows exit codes are full 32-bit values, blending several distinct categories: Without the program's documentation, you cannot disambiguate

These are STILL_ACTIVE (thread) and STATUS_PENDING (process). Seeing them from GetExitCodeProcess means you called it before the process actually exited. This is a classic race.