WININET Functions

The table on this page is this study’s master list of functions that appear in the export directory of any known 32-bit build of WININET. It gives for each function just brief summaries of the applicable WININET versions and of the function’s status with respect to Microsoft’s documentation. Additional explanatory notes follow the table.

Notes

Function names are reproduced from the export directory of the WININET.DLL executable, wherever possible. For functions that are not exported by name, i.e., are exported only by ordinal, from any known WININET version, names are inferred from symbol files that Microsoft supplies for customer support. The ordinal is given in brackets immediately after the function’s name.

It perhaps must be stressed that a function’s presence in the export directory does not mean that the function is implemented non-trivially or that it will work satisfactorily if called, just that it can be imported from other modules, and be called, for better or worse. That a function is exported from some version does not mean that Microsoft supports its use in that version.

Versions

The WININET versions shown for each function are inferred from a study of known releases, making reasonable assumptions about likely continuity, especially to suppose that a function will exist in future versions or that a function exists in all released builds of a version if no counter-example is yet known.

This study refers to applicable products and service packs in ascending order of versions and build numbers. Be aware that this is not chronological order.

Some functions exported from WININET exist earlier as exports from a URLCACHE.DLL which is known only from Internet Explorer 3.00. These functions are indicated above by the annotation “earlier in URLCACHE”.

Documentation Status

This study’s reference version of Microsoft’s documentation is the Microsoft Windows Software Development Kit (SDK) for Windows 7 and .NET Framework 3.51 Service Pack 1, apparently released in August 2009. The build date shown on the opening pages of this documentation is 22nd June 2009. That a function is not marked above as documented (or is marked on other pages as undocumented) does not mean for certain that Microsoft does not document it, just that I haven’t yet found where.

Choosing one reference edition is not ideal for all purposes. Functions inevitably will be added for versions released afterwards, and will typically not be listed above as documented until a new reference edition is adopted. There is also a loss of history. Of interest to many is that Microsoft sometimes does not document new functions immediately and even not until years have passed. That a function is marked above as documented does not mean it has always been documented, only that it is documented in the chosen reference edition. Of interest perhaps only to historians is that even documented functions are sometimes discontinued, meaning specifically that later versions do not export them. Do not rely on me to have searched old editions of the SDK or MSDN Library to find whether discontinued functions ever were documented.

Rather many WININET functions that are not formally documented are at least declared in an SDK header file (named WININETI.H). These are indicated above by the annotation “declared”.