log topic

CategoryLog

Simple log messages with priorities and categories. A message's SDL_LogPriority signifies how important the message is. A message's SDL_LogCategory signifies from what domain it belongs to. Every category has a minimum priority specified: when a message belongs to that category, it will only be sent out if it has that minimum priority or higher.

SDL's own logs are sent below the default priority threshold, so they are quiet by default.

You can change the log verbosity programmatically using SDL_SetLogPriority() or with SDL_SetHint(SDL_HINT_LOGGING, ...), or with the "SDL_LOGGING" environment variable. This variable is a comma separated set of category=level tokens that define the default logging levels for SDL applications.

The category can be a numeric category, one of "app", "error", "assert", "system", "audio", "video", "render", "input", "test", or * for any unspecified category.

The level can be a numeric level, one of "trace", "verbose", "debug", "info", "warn", "error", "critical", or "quiet" to disable that category.

You can omit the category if you want to set the logging level for all categories.

If this hint isn't set, the default log levels are equivalent to:

app=info,assert=warn,test=verbose,*=error

Here's where the messages go on different platforms:

  • Windows: debug output stream
  • Android: log output
  • Others: standard error output (stderr)

You don't need to have a newline (\n) on the end of messages, the functions will do that for you. For consistent behavior cross-platform, you shouldn't have any newlines in messages, such as to log multiple lines in one call; unusual platform-specific behavior can be observed in such usage. Do one log call per line instead, with no newlines in messages.

Each log call is atomic, so you won't see log messages cut off one another when logging from multiple threads.

Functions

sdlGetDefaultLogOutputFunction() → Pointer<NativeFunction<SdlLogOutputFunction>> log
Get the default log output function.
sdlGetLogOutputFunction(Pointer<Pointer<NativeFunction<SdlLogOutputFunction>>> callback, Pointer<Pointer<NativeType>> userdata) → void log
Get the current log output function.
sdlGetLogPriority(int category) → int log
Get the priority of a particular log category.
sdlLog(String? fmt) → void log
Log a message with SDL_LOG_CATEGORY_APPLICATION and SDL_LOG_PRIORITY_INFO.
sdlLogCritical(int category, String? fmt) → void log
Log a message with SDL_LOG_PRIORITY_CRITICAL.
sdlLogDebug(int category, String? fmt) → void log
Log a message with SDL_LOG_PRIORITY_DEBUG.
sdlLogError(int category, String? fmt) → void log
Log a message with SDL_LOG_PRIORITY_ERROR.
sdlLogInfo(int category, String? fmt) → void log
Log a message with SDL_LOG_PRIORITY_INFO.
sdlLogMessage(int category, int priority, String? fmt) → void log
Log a message with the specified category and priority.
sdlLogMessageV(int category, int priority, String? fmt) → void log
Log a message with the specified category and priority.
sdlLogTrace(int category, String? fmt) → void log
Log a message with SDL_LOG_PRIORITY_TRACE.
sdlLogVerbose(int category, String? fmt) → void log
Log a message with SDL_LOG_PRIORITY_VERBOSE.
sdlLogWarn(int category, String? fmt) → void log
Log a message with SDL_LOG_PRIORITY_WARN.
sdlResetLogPriorities() → void log
Reset all priorities to default.
sdlSetLogOutputFunction(Pointer<NativeFunction<SdlLogOutputFunction>> callback, Pointer<NativeType> userdata) → void log
Replace the default log output function with one of your own.
sdlSetLogPriorities(int priority) → void log
Set the priority of all log categories.
sdlSetLogPriority(int category, int priority) → void log
Set the priority of a particular log category.
sdlSetLogPriorityPrefix(int priority, String? prefix) → bool log
Set the text prepended to log messages of a given priority.