Name

inflateInit_ — Initializes the decompression system.

Library

Libz.lib

Synopsis

#include <zlib.h>

int inflateInit_(z_streamp stream, const char * version, int stream_size);

Return Value

On success, the inflateInit_() function shall return Z_OK. Otherwise, inflateInit_() shall return a value as described below to indicate the error.

Detailed Description

The inflateInit_() function shall initialize the decompression system. On entry, stream shall refer to a user supplied z_stream object (a z_stream_s structure). The following fields shall be set on entry:

`zalloc`		a pointer to an alloc_func function, used to allocate state information. If this is `NULL`, a default allocation function will be used.
`zfree`		a pointer to a free_func function, used to free memory allocated by the `zalloc` function. If this is `NULL` a default free function will be used.
`opaque`		If `alloc_func` is not `NULL`, `opaque` is a user supplied pointer to data that will be passed to the `alloc_func` and `free_func` functions.

If the version requested is not compatible with the version implemented, or if the size of the z_stream_s structure provided in stream_size does not match the size in the library implementation, inflateInit_() shall fail, and return Z_VERSION_ERROR.

The inflateInit_() function is not in the source standard; it is only in the binary standard. Source applications should use the inflateInit() macro.

The inflateInit_() shall be equivalent to inflateInit2_(strm, DEF_WBITS, version, stream_size);

Examples

To initialize the decompression system:

#include <stdio.h> 
#include <zlib.h> 
void InflateInit_( )
{ 
    z_stream d_stream; 
    const char * version;
    d_stream.zalloc = (alloc_func)0;
    d_stream.zfree = (free_func)0;
    d_stream.opaque = (voidpf)0;
    const char hello[] = "hello, hello!";
    Byte *compr, *uncompr;
    uLong comprLen = 20*sizeof(int); 
    uLong uncomprLen = comprLen;
    compr    = (Byte*)calloc((uInt)comprLen, 1);
    uncompr  = (Byte*)calloc((uInt)uncomprLen, 1);   
    uLong len = (uLong)strlen(hello)+1;
    compress(compr, &comprLen, (const Bytef*)hello, len);   
    d_stream.next_in  = compr;
    d_stream.avail_in = 0;
    d_stream.next_out = uncompr;
    version=zlibVersion();
    int ret = inflateInit_(&d_stream,(char*)version, sizeof(d_stream));
    inflateEnd(&d_stream);
    free(compr);
    free(uncompr);       
}

Errors

On error, inflateInit_() shall return one of the following error indicators:

`Z_STREAM_ERROR`		Invalid parameter.
`Z_MEM_ERROR`		Insufficient memory available.
`Z_VERSION_ERROR`		The version requested is not compatible with the library version, or the z_stream size differs from that used by the library.

In addition, the msg field of the strm may be set to an error message.

Feedback

For additional information or queries on this page send feedback