Assorted Experience

Problem: Python's gzip module is awesome, but poses a problem when we wish to report reading progress along a compressed file: .tell() returns the total bytes read but we usually only have the compressed size of the total file available, e.g. via os.path.getsize. Solution: One trick is probably to extract the original size of the gzipped file from the last 4 bytes in the file , but, there are interesting caveats to this. Another method, slightly more principled, is to use .raw.fileobj.tell which, interestingly, reports the position on the compressed file, rather than the uncompressed stream.

Problem: After moving data from a Time machine backup to a new Mac (EDIT) Actually, I copied the data to a NTFS drive and then back to a Mac, so the blame goes to NTFS, all files in a repository show up as changed files under git, even though a diff proves that their contents are unchanged. Solution: From a tip here, it turns out that it's related to file mode (and other metadata) changes which may occur during such a restore operation (for example the UID of the user may change, I guess) the solution is to tell git to ignore the file mode git config core.fileMode false