# QairtLog Note Some methods in this module are not yet implemented in the current release and will raise an exception if called. See the C API for full functionality. **Include:** `#include "QairtCppApi/QairtLog.hpp"` C++ wrapper for the QAIRT logging API. A Backend must be created before constructing a Log object. - namespace qairt - Enums - enum class LogError : std::underlying\_type\_t<[QairtLog\_Error\_t](https://docs.qualcomm.com/doc/80-63442-10/topic/QairtLog.html#_CPPv416QairtLog_Error_t)> - Error codes returned by QAIRT logging operations. | Enumerator | Description | | --- | --- | | `NoError` | Operation succeeded. | | `MemAlloc` | Memory allocation failure. | | `Initialization` | [Log](https://docs.qualcomm.com/doc/80-63442-10/topic/cpp-api_QairtLog.html#classqairt_1_1Log) initialization failed. | | `InvalidArgument` | An argument to the operation was invalid. | | `InvalidHandle` | The provided handle is not valid. | | `Undefined` | An undefined or unknown error occurred. | *Values:* - enumerator NoError = [QAIRT\_LOG\_NO\_ERROR](https://docs.qualcomm.com/doc/80-63442-10/topic/QairtLog.html#_CPPv4N16QairtLog_Error_t18QAIRT_LOG_NO_ERRORE) - - enumerator MemAlloc = [QAIRT\_LOG\_ERROR\_MEM\_ALLOC](https://docs.qualcomm.com/doc/80-63442-10/topic/QairtLog.html#_CPPv4N16QairtLog_Error_t25QAIRT_LOG_ERROR_MEM_ALLOCE) - - enumerator Initialization = [QAIRT\_LOG\_ERROR\_INITIALIZATION](https://docs.qualcomm.com/doc/80-63442-10/topic/QairtLog.html#_CPPv4N16QairtLog_Error_t30QAIRT_LOG_ERROR_INITIALIZATIONE) - - enumerator InvalidArgument = [QAIRT\_LOG\_ERROR\_INVALID\_ARGUMENT](https://docs.qualcomm.com/doc/80-63442-10/topic/QairtLog.html#_CPPv4N16QairtLog_Error_t32QAIRT_LOG_ERROR_INVALID_ARGUMENTE) - - enumerator InvalidHandle = [QAIRT\_LOG\_ERROR\_INVALID\_HANDLE](https://docs.qualcomm.com/doc/80-63442-10/topic/QairtLog.html#_CPPv4N16QairtLog_Error_t30QAIRT_LOG_ERROR_INVALID_HANDLEE) - - enumerator Undefined = [QAIRT\_LOG\_ERROR\_UNDEFINED](https://docs.qualcomm.com/doc/80-63442-10/topic/QairtLog.html#_CPPv4N16QairtLog_Error_t25QAIRT_LOG_ERROR_UNDEFINEDE) - - enum class LogLevel : std::underlying\_type\_t<[QairtLog\_Level\_t](https://docs.qualcomm.com/doc/80-63442-10/topic/QairtLog.html#_CPPv416QairtLog_Level_t)> - Verbosity levels for QAIRT log output. | Enumerator | Description | | --- | --- | | `Error` | Error conditions only. | | `Warn` | Warnings and error conditions. | | `Info` | Informational messages, warnings, and errors. | | `Verbose` | Detailed trace messages and all lower-severity output. | | `Debug` | Reserved for developer debugging; most verbose level. | | `Max` | Sentinel value; enables all log output. | *Values:* - enumerator Error = [QAIRT\_LOG\_LEVEL\_ERROR](https://docs.qualcomm.com/doc/80-63442-10/topic/QairtLog.html#_CPPv4N16QairtLog_Level_t21QAIRT_LOG_LEVEL_ERRORE) - - enumerator Warn = [QAIRT\_LOG\_LEVEL\_WARN](https://docs.qualcomm.com/doc/80-63442-10/topic/QairtLog.html#_CPPv4N16QairtLog_Level_t20QAIRT_LOG_LEVEL_WARNE) - - enumerator Info = [QAIRT\_LOG\_LEVEL\_INFO](https://docs.qualcomm.com/doc/80-63442-10/topic/QairtLog.html#_CPPv4N16QairtLog_Level_t20QAIRT_LOG_LEVEL_INFOE) - - enumerator Verbose = [QAIRT\_LOG\_LEVEL\_VERBOSE](https://docs.qualcomm.com/doc/80-63442-10/topic/QairtLog.html#_CPPv4N16QairtLog_Level_t23QAIRT_LOG_LEVEL_VERBOSEE) - - enumerator Debug = [QAIRT\_LOG\_LEVEL\_DEBUG](https://docs.qualcomm.com/doc/80-63442-10/topic/QairtLog.html#_CPPv4N16QairtLog_Level_t21QAIRT_LOG_LEVEL_DEBUGE) - - enumerator Max = [QAIRT\_LOG\_LEVEL\_MAX](https://docs.qualcomm.com/doc/80-63442-10/topic/QairtLog.html#_CPPv4N16QairtLog_Level_t19QAIRT_LOG_LEVEL_MAXE) - - class Log : public [qairt](https://docs.qualcomm.com/doc/80-63442-10/topic/cpp-api_QairtLog.html#_CPPv45qairt)::ApiType<[Log](https://docs.qualcomm.com/doc/80-63442-10/topic/cpp-api_QairtLog.html#_CPPv4N5qairt3LogE), [QairtLog\_V1\_t](https://docs.qualcomm.com/doc/80-63442-10/topic/QairtLog.html#_CPPv413QairtLog_V1_t)> - *#include <QairtLog.hpp>* Wrapper for a QAIRT [Log](https://docs.qualcomm.com/doc/80-63442-10/topic/cpp-api_QairtLog.html#classqairt_1_1Log) handle. Obtained via @ref Api::make(). Copy to clipboard Public Functions - Log() noexcept = default - - Log(const [Log](https://docs.qualcomm.com/doc/80-63442-10/topic/cpp-api_QairtLog.html#_CPPv4N5qairt3Log3LogERK3Log)&) = delete - - Log([Log](https://docs.qualcomm.com/doc/80-63442-10/topic/cpp-api_QairtLog.html#_CPPv4N5qairt3Log3LogERR3Log)&&) noexcept = default - - [Log](https://docs.qualcomm.com/doc/80-63442-10/topic/cpp-api_QairtLog.html#_CPPv4N5qairt3LogE) &operator=(const [Log](https://docs.qualcomm.com/doc/80-63442-10/topic/cpp-api_QairtLog.html#_CPPv4N5qairt3LogE)&) = delete - - [Log](https://docs.qualcomm.com/doc/80-63442-10/topic/cpp-api_QairtLog.html#_CPPv4N5qairt3LogE) &operator=([Log](https://docs.qualcomm.com/doc/80-63442-10/topic/cpp-api_QairtLog.html#_CPPv4N5qairt3LogE)&&) noexcept = default - - inline void setLogLevel([QairtLog\_Level\_t](https://docs.qualcomm.com/doc/80-63442-10/topic/QairtLog.html#_CPPv416QairtLog_Level_t) level) - Set the verbosity level for this log instance. See also [QairtLog\_setLogLevel](https://docs.qualcomm.com/doc/80-63442-10/topic/QairtLog.html#QairtLog_8h_1ac26870e03f118b0802d57564ad0b8d77) - Parameters - **level** – **[in]** Maximum log verbosity. - Throws - [qairt](https://docs.qualcomm.com/doc/80-63442-10/topic/cpp-api_QairtLog.html#_CPPv45qairt)::[Exception](https://docs.qualcomm.com/doc/80-63442-10/topic/QairtApi.html#_CPPv4N5qairt9ExceptionE) – on invalid handle. Private Functions - inline Log(const std::shared\_ptr<ApiTable> &apiTable, [LogCallback](https://docs.qualcomm.com/doc/80-63442-10/topic/cpp-api_QairtLog.html#_CPPv4N5qairt11LogCallbackE) &&callback, [LogLevel](https://docs.qualcomm.com/doc/80-63442-10/topic/cpp-api_QairtLog.html#_CPPv4N5qairt8LogLevelE) level, void \*userData = nullptr) - - inline Log(const std::shared\_ptr<ApiTable> &apiTable, [QairtLog\_CallbackFn\_t](https://docs.qualcomm.com/doc/80-63442-10/topic/QairtLog.html#_CPPv421QairtLog_CallbackFn_t) callbackFn, [QairtLog\_Level\_t](https://docs.qualcomm.com/doc/80-63442-10/topic/QairtLog.html#_CPPv416QairtLog_Level_t) level, void \*userData = nullptr) - Private Members - [LogCallback](https://docs.qualcomm.com/doc/80-63442-10/topic/cpp-api_QairtLog.html#_CPPv4N5qairt11LogCallbackE) m\_callback - Callback function pointer for this log instance. Friends - *friend class* Api - class LogCallback : public [qairt](https://docs.qualcomm.com/doc/80-63442-10/topic/cpp-api_QairtLog.html#_CPPv45qairt)::ApiType<[LogCallback](https://docs.qualcomm.com/doc/80-63442-10/topic/cpp-api_QairtLog.html#_CPPv4N5qairt11LogCallbackE), [QairtLog\_CallbackV1\_t](https://docs.qualcomm.com/doc/80-63442-10/topic/QairtLog.html#_CPPv421QairtLog_CallbackV1_t)> - *#include <QairtLog.hpp>* Wrapper for a QAIRT log callback function handle. Public Functions - LogCallback() noexcept = default - - LogCallback(const [LogCallback](https://docs.qualcomm.com/doc/80-63442-10/topic/cpp-api_QairtLog.html#_CPPv4N5qairt11LogCallback11LogCallbackERK11LogCallback)&) = delete - - LogCallback([LogCallback](https://docs.qualcomm.com/doc/80-63442-10/topic/cpp-api_QairtLog.html#_CPPv4N5qairt11LogCallback11LogCallbackERR11LogCallback)&&) noexcept = default - - [LogCallback](https://docs.qualcomm.com/doc/80-63442-10/topic/cpp-api_QairtLog.html#_CPPv4N5qairt11LogCallbackE) &operator=(const [LogCallback](https://docs.qualcomm.com/doc/80-63442-10/topic/cpp-api_QairtLog.html#_CPPv4N5qairt11LogCallbackE)&) = delete - - [LogCallback](https://docs.qualcomm.com/doc/80-63442-10/topic/cpp-api_QairtLog.html#_CPPv4N5qairt11LogCallbackE) &operator=([LogCallback](https://docs.qualcomm.com/doc/80-63442-10/topic/cpp-api_QairtLog.html#_CPPv4N5qairt11LogCallbackE)&&) noexcept = default - Private Functions - inline LogCallback(const std::shared\_ptr<ApiTable> &apiTable, [QairtLog\_CallbackFn\_t](https://docs.qualcomm.com/doc/80-63442-10/topic/QairtLog.html#_CPPv421QairtLog_CallbackFn_t) callbackFn) - Friends - *friend class* Api - *friend class* Log - *friend class* SystemLog Last Published: Jun 04, 2026 [Previous Topic QairtProfile](https://docs.qualcomm.com/bundle/publicresource/80-63442-10/topics/cpp-api_QairtProfile.md) [Next Topic QairtSignal](https://docs.qualcomm.com/bundle/publicresource/80-63442-10/topics/cpp-api_QairtSignal.md)