Name

gzsetparams — Sets the compression level and compression strategy on the compressed file stream referenced by file.

Library

Libz.lib

Synopsis

#include <zlib.h>
int gzsetparams (gzFile file, int level, int strategy);

Return Value

On success, the gzsetparams() function shall return Z_OK.

Detailed Description

The gzsetparams() function shall set the compression level and compression strategy on the compressed file stream referenced by file. The compressed file stream shall have been opened in a write mode. The level and strategy are as defined in deflateInit2_. If there is any data pending writing, it shall be flushed before the parameters are updated.

Examples

To set the compression level=Z_BEST_SPEED and compression strategy=Z_DEFAULT_STRATEGY on the compressed file stream referenced by file:

#include <stdio.h>
#include <zlib.h>

void Gzsetparams( )
{
    const char hello[] = "hello, hello!";
    int len = (int)strlen(hello)+1;
    gzFile file;
    const char * fname = TESTFILE;
    file = gzopen(fname, "wb");
    gzputc(file, 'h');
    int u = gzsetparams(file, Z_BEST_SPEED, Z_DEFAULT_STRATEGY);
    int err= gzclose(file);
}

Errors

On error, gzsetparams() shall return one of the following error indications:

`Z_STREAM_ERROR`	Invalid parameter, or `file` not open for writing.
`Z_BUF_ERROR`	An internal inconsistency was detected while flushing the previous buffer.

Feedback

For additional information or queries on this page send feedback