The code set out below is not intended to be compiled, but is only intended as a very simplistic pointer to how to load and call the dll. You will have to look in the files referenced below for actual, working code. This code, as I understand it, is not callable from Visual Basic. This is due to a limitation on Visual Basic's part in that it cannot deal with pointers to functions, nor can it deal with pointers to structures very well. I know almost nothing about Visual Basic, and at this point, have little or no interest in learning much about it. There are two entry points that use the structure shown below: BOOL WINAPI ZpSetOptions(ZPOPT) and ZPOPT WINAPI ZpGetOptions(void) typedef struct { BOOL fSuffix = Currently not used by WiZ BOOL fEncrypt; = encrypt file BOOL fSystem; = include system and hidden files BOOL fVolume; = Include volume label BOOL fExtra; = Exclude extra attributes BOOL fNoDirEntries; = Do not add directory entries BOOL fDate; = Exclude files earlier than specified date BOOL fVerbose; = Mention oddities in zip file structure BOOL fQuiet; = Quiet operation BOOL fCRLF_LF; = Translate CR/LF to LF BOOL fLF_CRLF; = Translate LF to CR/LF BOOL fJunkDir; = Junk directory names BOOL fRecurse; = Recurse into subdirectories BOOL fGrow; = Allow appending to a zip file BOOL fForce; = Make entries using DOS names (k for Katz) BOOL fMove; = Delete files added or updated in zip file BOOL fDeleteEntries; = Delete files from zip file BOOL fUpdate; = Update zip file--overwrite only if newer BOOL fFreshen; = Freshen zip file--overwrite only BOOL fJunkSFX; = Junk SFX prefix BOOL fLatestTime; = Set zip file time to time of latest file in it BOOL fComment; = Put comment in zip file BOOL fOffsets; = Update archive offsets for SFX files BOOL fPrivilege; = Save privileges BOOL fEncryption = read only option, true if encryption supported, false otherwise. int fRepair; = 1 => fix archive, 2 => try harder to fix char fLevel; = Compression level (0 - 9) char Date[7]; = Date to include files after char szRootDir[256]; = Directory to use as base for zipping } ZPOPT, _far *LPZPOPT BOOL WINAPI ZpSetOptions(ZPOPT) This call will simply set the options in the zip dll until such time as another call to this function is made. This must be made before the initial call to make or update an archive. ZPOPT WINAPI ZpGetOptions(void) The call will return the above structure from the dll, with the fEncryption flag set to the appropriate value based on whether encryption is supported in this dll or not. It is currently used in WiZ only to determine if encryption is actually supported. The main entry point is ZpArchive(ZCL C) where the structure shown below is passed to the DLL when it is called. typedef struct { int argc; = Count of files to zip LPSTR lpszZipFN; = Archive file name char **FNV; = file names to zip up. Think of this an argv } ZCL, _far *LPZCL; For examples of how the actual calls to the dll were set up in WiZ, look in the file makezip.c in the WiZ source directory. For examples of how the actual loading and unloading of the dll's themselves was done, look in wizmain.c in the WiZ source directory. Note that WiZ looks specifically for a particular version number of the dll, and also expects to find the company name to be Info-ZIP. This is to protect from getting different versions of the dll loaded, with resulting unknown behavior. There is a very simplistic example of how to load and call into the dll in example.c and example.h. Note that this example does not implement any command line switches at all, and is merely intended as a guide for those brave enough to enter a new world. There are four additional (at the moment) entry points: ZpInit, defined as int WINAPI ZpInit(ZIPUSERFUNCTIONS far * lpZipUserFunc); where ZIPUSERFUNCTIONS is defined as below. ZpInitVB, defined as int WINAPI ZpInitVB(ZIPUSERFUNCTIONS_VB) where ZIPUSERFUNCTIONS_VB is defined as: typedef struct { HINSTANCE hInstance; char print[80]; char comment[80]; char password[80]; } ZIPUSERFUNCTIONS_VB, far *LPZIPUSERFUNCTIONS_VB; ZpInitVB is designed to be used only by Visual Basic users, as it is my understanding that VB doesn't talk pointers to functions. Hence what is required here is to pass in the exact name of the functions for printing, passwords and handling comments. These functions must also be exported by the VB application. NOTE that this function has been tested under 'C', but has not with VB. I have no idea if this will truly work. ZpVersion, defined as ZpVer * ZpVersion(void); where ZpVer is defined as: typedef struct _ZpVer { ulg structlen; /* length of the struct being passed */ ulg flag; /* bit 0: is_beta bit 1: uses_zlib */ char *betalevel; /* e.g., "g BETA" or "" */ char *date; /* e.g., "4 Sep 95" (beta) or "4 September 1995" */ char *zlib_version; /* e.g., "0.95" or NULL */ _zip_version_type zip; _zip_version_type os2dll; _zip_version_type windll; } ZpVer; See api.c for exactly what ZpVersion does, but the short version of what it does is return the unzip and dll versions in the ZpVer structure. The structure typedef's are in api.h The typedef's for the function pointers in the structure ZIPUSERFUNCTIONS are shown immediately below. typedef int (far *DLLPRNT) (FILE *, unsigned int, char *); typedef int (WINAPI DLLPASSWORD) (char *, char *, int, char *); typedef char far * (far *DLLCOMMENT) (LPSTR); typedef struct { DLLPRNT *print; = pointer to application's print function. DLLPASSWORD *password; = pointer to application's function for processing passwords. Called from ttyio.c DLLCOMMENT *comment; = pointer to application's function for processing comments. } ZIPUSERFUNCTIONS, far * LPZIPUSERFUNCTIONS; Last revised June 3, 1997. Mike White