201     gzFile gz;  local
204     gz = malloc(sizeof(struct gzFile_s));
205     if (gz == NULL)
207     gz->write = strchr(mode, 'w') != NULL;
208     gz->strm.zalloc = myalloc;
209     gz->strm.zfree = myfree;
210     gz->strm.opaque = Z_NULL;
211     if (gz->write)
212         ret = deflateInit2(&(gz->strm), -1, 8, 15 + 16, 8, 0);
214         gz->strm.next_in = 0;
215         gz->strm.avail_in = Z_NULL;
216         ret = inflateInit2(&(gz->strm), 15 + 16);
219         free(gz);
222     gz->file = path == NULL ? fdopen(fd, gz->write ? "wb" : "rb") :
223                               fopen(path, gz->write ? "wb" : "rb");
224     if (gz->file == NULL) {
225         gz->write ? deflateEnd(&(gz->strm)) : inflateEnd(&(gz->strm));
226         free(gz);
229     gz->err = 0;
230     gz->msg = "";
231     return gz;
236 int gzwrite(gz, buf, len)  in gzwrite()  argument
237     gzFile gz;  in gzwrite()
244     if (gz == NULL || !gz->write)
246     strm = &(gz->strm);
253         fwrite(out, 1, BUFLEN - strm->avail_out, gz->file);
260 int gzread(gz, buf, len)  in gzread()  argument
261     gzFile gz;  in gzread()
270     if (gz == NULL || gz->write)
272     if (gz->err)
274     strm = &(gz->strm);
278         got = fread(in, 1, 1, gz->file);
285             gz->err = Z_DATA_ERROR;
286             gz->msg = strm->msg;
297 int gzclose(gz)  in gzclose()  argument
298     gzFile gz;  in gzclose()
303     if (gz == NULL)
305     strm = &(gz->strm);
306     if (gz->write) {
313             fwrite(out, 1, BUFLEN - strm->avail_out, gz->file);
319     fclose(gz->file);
320     free(gz);
326 const char *gzerror(gz, err)  in gzerror()  argument
327     gzFile gz;  in gzerror()
330     *err = gz->err;
331     return gz->msg;