zlib gzclose: How to detect a successful file closure?

I have used zlib to compress a file. All works well. After the operation is complete, I call gzclose(file) to flush and close the zip file. According to the documentation, the gzclose returns an int which provides the success or failure of the gzclose operation. Since there can be many failure reasons, checking for each error code is not feasible for me. I opt to check for the success of the operation and handle error codes separately. I could not find the return code for successful gzclose in any of the documentation I referred.

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