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This section is a reference to the program definitions used by the Plug-in API. All program definitions are found in npapi.h.

Error Codes

Code Value Description
NPERR_NO_ERROR 0 No errors occurred.
NPERR_GENERIC_ERROR 1 Error with no specific error code occurred.
NPERR_INVALID_INSTANCE_ERROR 2 Invalid instance passed to the plug-in.
NPERR_INVALID_FUNCTABLE_ERROR 3 Function table invalid.
NPERR_MODULE_LOAD_FAILED_ERROR 4 Loading of plug-in failed.
NPERR_OUT_OF_MEMORY_ERROR 5 Memory allocation failed.
NPERR_INVALID_PLUGIN_ERROR 6 Plug-in missing or invalid.
NPERR_INVALID_PLUGIN_DIR_ERROR 7 Plug-in directory missing or invalid.
NPERR_INCOMPATIBLE_VERSION_ERROR 8 Versions of plug-in and Communicator do not match.
NPERR_INVALID_PARAM 9 Parameter missing or invalid.
NPERR_INVALID_URL 10 URL missing or invalid.
NPERR_FILE_NOT_FOUND 11 File missing or invalid.
NPERR_NO_DATA 12 Stream contains no data.
NPERR_STREAM_NOT_SEEKABLE 13 Seekable stream expected.

Result Codes

Constant Value Description
NPRES_DONE 0 (Most common): Completed normally; all data was sent to the instance.
NPRES_NETWORK_ERR 1 Stream failed due to problems with network, disk I/O, lack of memory, or other problems.
NPRES_USER_BREAK 2 User canceled stream directly by clicking the Stop button or indirectly by some action such as deleting the instance or initiating higher-priority network operations.

Plug-in Version Constants

Constant Value Description
NP_VERSION_MAJOR 0 Major version number; changes with major code release number.
NP_VERSION_MINOR 22 Minor version number; changes with point release number.

Version Feature Constants

NPVERS Constant: Version Feature Information Value Description
NPVERS_HAS_NOTIFICATION 9 Notification of completion.
NPVERS_68K_HAS_LIVECONNECT 11 LiveConnect (68K).
NPVERS_HAS_WINDOWLESS 11 Windowless plug-in.
NPVERS_HAS_XPCONNECT_SCRIPTING 13 Plug-in is scriptable using XPConnect.
NPVERS_HAS_NPRUNTIME_SCRIPTING 14 Plug-in is scriptable using NPRuntime.
NPVERS_HAS_FORM_VALUES 15 NPPVformValue NPPVariables are supported.
NPVERS_HAS_POPUPS_ENABLED_STATE 16 The NPN_PushPopupsEnabledState() and NPN_PopPopupsEnabledState() functions are supported.
NPVERS_HAS_RESPONSE_HEADERS 17 NPStreams have response headers for HTTP streams.
NPVERS_HAS_NPOBJECT_ENUM 18 The in question has an enumerate field, which lets you enumerate the properties of an of that class.

Document Tags and Contributors

 Last updated by: teoli,