Option Flags

The following list contains the options supported by InternetQueryOption and InternetSetOption. All valid option flags have a value greater than or equal to INTERNET_FIRST_OPTION and less than or equal to INTERNET_LAST_OPTION.

INTERNET_OPTION_ASYNC

Not currently implemented.

INTERNET_OPTION_ASYNC_ID

Not implemented.

INTERNET_OPTION_ASYNC_PRIORITY

Not currently implemented.

INTERNET_OPTION_BYPASS_EDITED_ENTRY

Sets or retrieves the Boolean value that determines if the system should check the network for newer content and overwrite edited cache entries if a newer version is found. If set to TRUE, the system will check the network for newer content and overwrite the edited cache entry with the newer version. The default is FALSE, which indicates that the edited cache entry should be used without checking the network. This is used by InternetQueryOption and InternetSetOption. It is valid only in Microsoft® Internet Explorer version 5 and later.

INTERNET_OPTION_CACHE_STREAM_HANDLE

No longer supported.

INTERNET_OPTION_CACHE_TIMESTAMPS

Retrieves an INTERNET_CACHE_TIMESTAMPS structure that contains the LastModified time and Expires time from the resource stored in the Internet cache. This value is used by InternetQueryOption.

INTERNET_OPTION_CALLBACK

Sets or retrieves the address of the callback function defined for this handle. This option can be used on all HINTERNET handles. Used by InternetQueryOption and InternetSetOption.

INTERNET_OPTION_CALLBACK_FILTER

Not currently implemented.

INTERNET_OPTION_CODEPAGE

Not currently implemented.

INTERNET_OPTION_CONNECT_BACKOFF

Not currently implemented.

INTERNET_OPTION_CONNECT_LIMIT

Not currently implemented.

INTERNET_OPTION_CONNECT_RETRIES

Sets or retrieves an unsigned long integer value that contains the retry count to use for Internet connection requests. If a connection attempt still fails after the specified number of tries, the request is canceled. The default is five retries. This option can be used on any HINTERNET handle, including a NULL handle. It is used by InternetQueryOption and InternetSetOption.

INTERNET_OPTION_CONNECT_TIME

Not currently implemented.

INTERNET_OPTION_CONNECT_TIMEOUT

Sets or retrieves an unsigned long integer value that contains the time-out value, in milliseconds, to use for Internet connection requests. If a connection request takes longer than this time-out value, the request is canceled. This option can be used on any HINTERNET handle, including a NULL handle. It is used by InternetQueryOption and InternetSetOption.

INTERNET_OPTION_CONNECTED_STATE

Sets or retrieves an unsigned long integer value that contains the connected state. This is used by InternetQueryOption and InternetSetOption.

INTERNET_OPTION_CONTEXT_VALUE

Sets or retrieves a DWORD_PTR that contains the address of the context value associated with this Internet handle. This option can be used on any HINTERNET handle. This is used by InternetQueryOption and InternetSetOption. Previously, this set the context value to the address stored in the DWORD(lpBuffer) pointer. This has been corrected so that the value stored in the buffer will be used and the INTERNET_OPTION_CONTEXT_VALUE flag will be assigned a new value. The old value, 10, has been preserved so that applications written for the old behavior are still supported.

INTERNET_OPTION_CONTROL_RECEIVE_TIMEOUT

Identical to INTERNET_OPTION_RECEIVE_TIMEOUT. This is used by InternetQueryOption and InternetSetOption.

INTERNET_OPTION_CONTROL_SEND_TIMEOUT

Identical to INTERNET_OPTION_SEND_TIMEOUT. This is used by InternetQueryOption and InternetSetOption.

INTERNET_OPTION_DATA_RECEIVE_TIMEOUT

Not implemented.

INTERNET_OPTION_DATA_SEND_TIMEOUT

Not implemented.

INTERNET_OPTION_DATAFILE_NAME

Retrieves a string value that contains the name of the file backing a downloaded entity. This flag is valid after InternetOpenUrl, FtpOpenFile, GopherOpenFile, or HttpOpenRequest has completed. It is used by InternetQueryOption and InternetSetOption.

INTERNET_OPTION_DIGEST_AUTH_UNLOAD

Causes the system to log off the Digest authentication SSPI package, purging all of the credentials created for the process. No buffer is required for this option. It is used by InternetSetOption.

INTERNET_OPTION_DISABLE_AUTODIAL

Not currently implemented.

INTERNET_OPTION_DISCONNECTED_TIMEOUT

Not currently implemented.

INTERNET_OPTION_END_BROWSER_SESSION

Flushes entries not in use from the password cache on the hard drive. Also resets the cache time used when the synchronization mode is once-per-session. No buffer is required for this option. This is used by InternetSetOption.

INTERNET_OPTION_ERROR_MASK

Sets an unsigned long integer value that contains the error masks that can be handled by the client application. This can be a combination of the following values:

INTERNET_ERROR_MASK_COMBINED_SEC_CERT: Indicates that the client application can handle security certificate error codes.
INTERNET_ERROR_MASK_INSERT_CDROM: Indicates that the client application can handle the ERROR_INTERNET_INSERT_CDROM error code.
INTERNET_ERROR_MASK_LOGIN_FAILURE_DISPLAY_ENTITY_BODY: Indicates that the client application can handle the ERROR_INTERNET_LOGIN_FAILURE_DISPLAY_ENTITY_BODY error code.

INTERNET_ERROR_MASK_NEED_MSN_SSPI_PKG

Not currently implemented.

INTERNET_OPTION_EXTENDED_ERROR

Retrieves an unsigned long integer value that contains a Microsoft® Windows® Sockets error code that was mapped to the ERROR_INTERNET_ error messages last returned in this thread context. This option is used on a NULL HINTERNET handle by InternetQueryOption.

INTERNET_OPTION_FROM_CACHE_TIMEOUT

Sets or retrieves an unsigned long integer value that contains the amount of time the system should wait for a response to a network request before checking the cache for a copy of the resource. If a network request takes longer than the time specified and the requested resource is available in the cache, the resource will be retrieved from the cache. This is used by InternetQueryOption and InternetSetOption.

INTERNET_OPTION_HANDLE_TYPE

Retrieves an unsigned long integer value that contains the type of the Internet handle passed in. This is used by InternetQueryOption on any HINTERNET handle. Possible return values include:

INTERNET_HANDLE_TYPE_CONNECT_FTP

INTERNET_HANDLE_TYPE_CONNECT_GOPHER

INTERNET_HANDLE_TYPE_CONNECT_HTTP

INTERNET_HANDLE_TYPE_FILE_REQUEST

INTERNET_HANDLE_TYPE_FTP_FILE

INTERNET_HANDLE_TYPE_FTP_FILE_HTML

INTERNET_HANDLE_TYPE_FTP_FIND

INTERNET_HANDLE_TYPE_FTP_FIND_HTML

INTERNET_HANDLE_TYPE_GOPHER_FILE

INTERNET_HANDLE_TYPE_GOPHER_FILE_HTML

INTERNET_HANDLE_TYPE_GOPHER_FIND

INTERNET_HANDLE_TYPE_GOPHER_FIND_HTML

INTERNET_HANDLE_TYPE_HTTP_REQUEST

INTERNET_HANDLE_TYPE_INTERNET

INTERNET_OPTION_HTTP_VERSION

Sets or retrieves an HTTP_VERSION_INFO structure that contains the HTTP version being supported. This must be used on a NULL handle. This is used by InternetQueryOption and InternetSetOption.

INTERNET_OPTION_IDLE_STATE

Not currently implemented.

INTERNET_OPTION_IGNORE_OFFLINE

Sets or retrieves whether the global offline flag should be ignored. No buffer is required for this option. This is used by InternetQueryOption and InternetSetOption. This value was introduced in Internet Explorer 5.

INTERNET_OPTION_KEEP_CONNECTION

Not currently implemented.

INTERNET_OPTION_LISTEN_TIMEOUT

Not currently implemented.

INTERNET_OPTION_MAX_CONNS_PER_SERVER

Sets or retrieves an unsigned long integer value that contains the maximum number of connections allowed per server. This is used by InternetQueryOption and InternetSetOption. This value was introduced in Internet Explorer 5.

INTERNET_OPTION_MAX_CONNS_PER_1_0_SERVER

Sets or retrieves an unsigned long integer value that contains the maximum number of connections allowed per HTTP/1.0 server. This is used by InternetQueryOption and InternetSetOption. This value was introduced in Internet Explorer 5.

INTERNET_OPTION_OFFLINE_MODE

Not currently implemented.

INTERNET_OPTION_OFFLINE_SEMANTICS

Not currently implemented.

INTERNET_OPTION_PARENT_HANDLE

Retrieves the parent handle to this handle. This option can be used on any HINTERNET handle by InternetQueryOption.

INTERNET_OPTION_PASSWORD

Sets or retrieves a string value that contains the password associated with a handle returned by InternetConnect. This is used by InternetQueryOption and InternetSetOption.

INTERNET_OPTION_PER_CONNECTION_OPTION

Sets or retrieves an INTERNET_PER_CONN_OPTION_LIST structure that specifies a list of options for a particular connection. This is used by InternetQueryOption and InternetSetOption. This option is only valid in Internet Explorer version 5 and later.

INTERNET_OPTION_POLICY

Not currently implemented.

INTERNET_OPTION_PROXY

Sets or retrieves an INTERNET_PROXY_INFO structure that contains the proxy information on an existing InternetOpen handle when the HINTERNET handle is not NULL. If the HINTERNET handle is NULL, the function sets or queries the global proxy information. This option can be used on the HINTERNET handle returned by InternetOpen. It is used by InternetQueryOption and InternetSetOption.

INTERNET_OPTION_PROXY_PASSWORD

Sets or retrieves a string value that contains the password currently being used to access the proxy. This is used by InternetQueryOption and InternetSetOption.

INTERNET_OPTION_PROXY_USERNAME

Sets or retrieves a string value that contains the user name currently being used to access the proxy. This is used by InternetQueryOption and InternetSetOption.

INTERNET_OPTION_READ_BUFFER_SIZE

Sets or retrieves an unsigned long integer value that contains the size of the read buffer. This option can be used on HINTERNET handles returned by FtpOpenFile, FtpFindFirstFile, and InternetConnect (FTP session only). This option is used by InternetQueryOption and InternetSetOption.

INTERNET_OPTION_RECEIVE_THROUGHPUT

Not currently implemented.

INTERNET_OPTION_RECEIVE_TIMEOUT

Sets or retrieves an unsigned long integer value that contains the time-out value, in milliseconds, to receive a response to a request. If the response takes longer than this time-out value, the request is canceled. This option can be used on any HINTERNET handle, including a NULL handle. It is used by InternetQueryOption and InternetSetOption.

INTERNET_OPTION_REFRESH

Causes the proxy information to be reread from the registry for a handle. No buffer is required. This option can be used on the HINTERNET handle returned by InternetOpen. It is used by InternetSetOption.

INTERNET_OPTION_RESET_URLCACHE_SESSION

Starts a new cache session for the process. No buffer is required. This is used by InternetSetOption.

INTERNET_OPTION_REQUEST_FLAGS

Retrieves an unsigned long integer value that contains the special status flags that indicate the status of the download currently in progress. This is used by InternetQueryOption. The INTERNET_OPTION_REQUEST_FLAGS option can be one of the following values:

INTERNET_REQFLAG_ASYNC	Not currently implemented.
INTERNET_REQFLAG_CACHE_WRITE_DISABLED	Internet request cannot be cached (an HTTPS request, for example).
INTERNET_REQFLAG_FROM_CACHE	Response came from the cache.
INTERNET_REQFLAG_NET_TIMEOUT	Internet request timed out.
INTERNET_REQFLAG_NO_HEADERS	Original response contained no headers.
INTERNET_REQFLAG_PASSIVE	Not currently implemented.
INTERNET_REQFLAG_VIA_PROXY	Request was made through a proxy.

INTERNET_OPTION_REQUEST_PRIORITY

Sets or retrieves an unsigned long integer value that contains the priority of requests competing for a connection on an HTTP handle. This is used by InternetQueryOption and InternetSetOption.

INTERNET_OPTION_SECONDARY_CACHE_KEY

Sets or retrieves a string value that contains the secondary cache key. This is used by InternetQueryOption and InternetSetOption.

INTERNET_OPTION_SECURITY_CERTIFICATE

Retrieves the certificate for an SSL/PCT (Secure Sockets Layer/Private Communications Technology) server into a formatted string. This is used by InternetQueryOption.

INTERNET_OPTION_SECURITY_CERTIFICATE_STRUCT

Retrieves the certificate for an SSL/PCT server into the INTERNET_CERTIFICATE_INFO structure. This is used by InternetQueryOption.

INTERNET_OPTION_SECURITY_FLAGS

Retrieves an unsigned long integer value that contains the security flags for a handle. This option is used by InternetQueryOption. It can be a combination of these values:

SECURITY_FLAG_128BIT	Identical to the preferred value SECURITY_FLAG_STRENGTH_STRONG. This is only returned in a call to InternetQueryOption.
SECURITY_FLAG_40BIT	Identical to the preferred value SECURITY_FLAG_STRENGTH_WEAK. This is only returned in a call to InternetQueryOption.
SECURITY_FLAG_56BIT	Identical to the preferred value SECURITY_FLAG_STRENGTH_MEDIUM. This is only returned in a call to InternetQueryOption.
SECURITY_FLAG_FORTEZZA	Indicates Fortezza has been used to provide secrecy, authentication, and/or integrity for the specified connection.
SECURITY_FLAG_IETFSSL4	Not currently implemented.
SECURITY_FLAG_IGNORE_CERT_CN_INVALID	Ignores the ERROR_INTERNET_SEC_CERT_CN_INVALID error message.
SECURITY_FLAG_IGNORE_CERT_DATE_INVALID	Ignores the ERROR_INTERNET_SEC_CERT_DATE_INVALID error message.
SECURITY_FLAG_IGNORE_REDIRECT_TO_HTTP	Ignores the ERROR_INTERNET_HTTPS_TO_HTTP_ON_REDIR error message.
SECURITY_FLAG_IGNORE_REDIRECT_TO_HTTPS	Ignores the ERROR_INTERNET_HTTP_TO_HTTPS_ON_REDIR error message.
SECURITY_FLAG_IGNORE_REVOCATION	Ignores certificate revocation problems.
SECURITY_FLAG_IGNORE_UNKNOWN_CA	Ignores unknown certificate authority problems.
SECURITY_FLAG_IGNORE_WRONG_USAGE	Ignores incorrect usage problems.
SECURITY_FLAG_NORMALBITNESS	Identical to the value SECURITY_FLAG_STRENGTH_WEAK. This is only returned in a call to InternetQueryOption.
SECURITY_FLAG_PCT	Not currently implemented.
SECURITY_FLAG_PCT4	Not currently implemented.
SECURITY_FLAG_SECURE	Uses secure transfers. This is only returned in a call to InternetQueryOption.
SECURITY_FLAG_SSL	Not currently implemented.
SECURITY_FLAG_SSL3	Not currently implemented.
SECURITY_FLAG_STRENGTH_MEDIUM	Uses medium (56-bit) encryption. This is only returned in a call to InternetQueryOption.
SECURITY_FLAG_STRENGTH_STRONG	Uses strong (128-bit) encryption. This is only returned in a call to InternetQueryOption.
SECURITY_FLAG_STRENGTH_WEAK	Uses weak (40-bit) encryption. This is only returned in a call to InternetQueryOption.
SECURITY_FLAG_UNKNOWNBIT	The bit size used in the encryption is unknown. This is only returned in a call to InternetQueryOption.

INTERNET_OPTION_SECURITY_KEY_BITNESS

Retrieves an unsigned long integer value that contains the bit size of the encryption key. The larger the number, the greater the encryption strength being used. This is used by InternetQueryOption.

INTERNET_OPTION_SECURITY_SELECT_CLIENT_CERT

Sets an unsigned long integer value that contains the client certification. This is used by InternetSetOption.

INTERNET_OPTION_SEND_THROUGHPUT

Not currently implemented.

INTERNET_OPTION_SEND_TIMEOUT

Sets or retrieves an unsigned long integer value that contains the time-out value, in milliseconds, to send a request. If the send takes longer than this time-out value, the send is canceled. This option can be used on any HINTERNET handle, including a NULL handle. It is used by InternetQueryOption and InternetSetOption.

INTERNET_OPTION_SETTINGS_CHANGED

Informs the system that the registry settings have been changed so that it will check the settings on the next call to InternetConnect. This is used by InternetSetOption.

INTERNET_OPTION_URL

Retrieves a string value that contains the full URL of a downloaded resource. If the original URL contained any extra information (such as search strings or anchors), or if the call was redirected, the URL returned will differ from the original. This option is valid on HINTERNET handles returned by InternetOpenUrl, FtpOpenFile, GopherOpenFile, or HttpOpenRequest. It is used by InternetQueryOption.

INTERNET_OPTION_USER_AGENT

Sets or retrieves the user agent string on handles supplied by InternetOpen and used in subsequent HttpSendRequest functions, as long as it is not overridden by a header added by HttpAddRequestHeaders or HttpSendRequest. This is used by InternetQueryOption and InternetSetOption.

INTERNET_OPTION_USERNAME

Sets or retrieves a string that contains the user name associated with a handle returned by InternetConnect. This is used by InternetQueryOption and InternetSetOption.

INTERNET_OPTION_VERSION

Retrieves an INTERNET_VERSION_INFO structure that contains the version number of Wininet.dll. This option can be used on a NULL HINTERNET handle by InternetQueryOption.

INTERNET_OPTION_WRITE_BUFFER_SIZE

Sets or retrieves an unsigned long integer value that contains the size of the write buffer. This option can be used on HINTERNET handles returned by FtpOpenFile and InternetConnect (FTP session only). It is used by InternetQueryOption and InternetSetOption.