This may have some advantages. When it is done, automatic compression is turned on again for the temporary file, and the temporary file is renamed to replace the original file. Also, the compression is done in the user space. Some people may consider it is better. This may be not possible if the file system is completely full.
Valid algorithms are the same as for the .B chattr utility.
Valid sizes are the same as for the .B chattr utility. If this flag is not used, .B e2compress will stop if the input file has more than one link, or if the temporary file already exists. If this flag is used, .B e2compress will continue. No verification will be performed when you use this flag. Display some statistics about clusters.