Error Codes

Enumerations
enum	CX_ERROR {   CX_Success = 0 , CX_Unspecified , CX_InvalidArgument , CX_AccessDenied ,   CX_FileNotFound , CX_AlreadyExists , CX_IsDirectory , CX_ReadOnly ,   CX_Range , CX_NotSupported }

Functions
const char *	cxErrMsg (int err)

Variables
_Thread_local int	cxerr

Detailed Description

Thread-local error code system for functions that cannot return error values.

The cxerr facility provides a thread-safe error reporting mechanism similar to the standard errno, but integrated into the CX framework. Functions that need to report errors but cannot return an error code (e.g., functions returning pointers or having other return value semantics) can set cxerr to indicate the reason for failure.

Key characteristics:

• Thread-local storage - each thread has independent error state
• Zero (CX_Success) indicates success
• Must be explicitly checked after operations that may fail
• Not automatically cleared - check immediately after the failing operation

Typical usage pattern:

cxerr = CX_Success;  // Clear error before operation
float val = strToFloat32(_SL("invalid"));
if (cxerr != CX_Success) {
    logError(_SL("Conversion failed: %")), cxErrMsg(cxerr));
}

Functions should document when they set cxerr on failure.

Enumeration Type Documentation

CX_ERROR

enum CX_ERROR

Standard CX error codes

Error codes used throughout the CX framework. Functions set cxerr to one of these values to indicate specific error conditions.

Enumerator
CX_Success	Operation completed successfully (no error)
CX_Unspecified	Unknown or unspecified error occurred.
CX_InvalidArgument	Function argument is invalid or malformed.
CX_AccessDenied	Permission denied or access not allowed.
CX_FileNotFound	Requested file or resource does not exist.
CX_AlreadyExists	File or resource already exists; refusing to overwrite.
CX_IsDirectory	Attempted to treat a directory as a file.
CX_ReadOnly	Attempted to write to read-only path or resource.
CX_Range	Value is out of valid range.
CX_NotSupported	Operation is not supported on this platform.

Definition at line 50 of file error.h.

Function Documentation

cxErrMsg()

const char * cxErrMsg

(

int

err

)

Get human-readable error message for an error code

Parameters

err	Error code from CX_ERROR enum

Returns

Constant string describing the error

Returns a descriptive message for the given error code. Useful for logging or displaying error information to users.

if (cxerr != CX_Success) {
    printf("Error: %s\n", cxErrMsg(cxerr));
}

Variable Documentation

cxerr

_Thread_local int cxerr

extern

Thread-local error code

Set by functions to indicate error conditions. Check this variable after calling functions that document cxerr usage. Always CX_Success (0) when no error occurred.