Add a way to decompress to file descriptor (pipe) directly

[Raimo33]

i can see there are ways to decompress from and compress to an fd. but why not add a compress from and decompress to?
this way i could directly decompress and write to the write end of a pipe_fd without intermediate buffers.
scenario:

• http response arrives, it is parsed and put in a big body buffer
• pipe() and fork()
• child decompresses to the write end of the pipe
• parent interprets decompressed data at the same time from the read end of the pipe

[madler]

What existing ways are you referring to?

[Raimo33]

ZEXTERN int ZEXPORT gzread(gzFile file, voidp buf, unsigned len);
"Read and decompress up to len uncompressed bytes from file into buf. If the input file is not in gzip format, gzread copies the given number of bytes into the buffer directly from the file."

ZEXTERN int ZEXPORT gzwrite(gzFile file, voidpc buf, unsigned len);
"Compress and write the len uncompressed bytes at buf to file. gzwrite returns the number of uncompressed bytes written or 0 in case of error."

https://www.zlib.net/manual.html

[madler]

this way i could directly decompress and write to the write end of a pipe_fd without intermediate buffers

The inflate and deflate functions operate entirely in memory, and can easily be used for this purpose. Though, of course, there are always "intermediate buffers". gzread and gzwrite have intermediate buffers.

I do not plan to add reverse gzread and gzwrite routines.