gzwrite

Name

gzwrite -- write to a compressed file

Synopsis

#include <zlib.h>

int gzwrite (gzFile file, voidpc buf, unsigned int len);

Description

The gzwrite() function shall write data to the compressed file referenced by file, which shall have been opened in a write mode (see gzopen() and gzdopen()). On entry, buf shall point to a buffer containing len bytes of uncompressed data. The gzwrite() function shall compress this data and write it to file. The gzwrite() function shall return the number of uncompressed bytes actually written.

Return Value

On success, gzwrite() shall return the number of uncompressed bytes actually written to file. On error gzwrite() shall return a value less than or equal to 0. Applications may examine the cause using gzerror().

Errors

On error, gzwrite() shall set the error number associated with the stream identified by file to indicate the error. Applications should use gzerror() to access this error value.

Z_ERRNO 

An underlying base library function has indicated an error. The global variable errno may be examined for further information.

Z_STREAM_ERROR 

The stream is invalid, is not open for writing, or is in an invalid state.

Z_BUF_ERROR 

no compression progress is possible (see deflate()).

Z_MEM_ERROR 

Insufficient memory available to compress.