savelog [-m mode] [-u user] [-g group] [-t] [-p] [-c cycle] [-l] [-j] [-J] [-1 .. -9] [-C] [-d] [-l] [-r rolldir] [-n] [-q] [-D dateformat] file ...
The savelog command saves and optionally compresses old copies of files. Older versions of file are named:
If the file does not exist and -t was given, it will be created.
For files that do exist and have lengths greater than zero, the following actions are performed:
For xz no strength option is set, and xz decides on the default based on the total amount of physical RAM. Note that xz can use a very large amount of memory for the higher compression levels.
If a process is still writing to file.0, and savelog moves it to file.1 and compresses it, data could be lost.