unzstd:tldr:d8aec

The command you provided does not have proper syntax. It is missing separator characters ('|' or ';' or '&&' etc.) between the filenames, which are needed to separate different commands. Assuming you meant separate commands, the command could be interpreted as:

unzstd ${filename1} -ztd ${filename2} -ztd ---

Let's break down this corrected command:

• unzstd is the command used to decompress files that were compressed using the Zstandard algorithm. Zstandard (also known as Zstd) is a lossless data compression algorithm developed by Facebook.

• ${filename1} and ${filename2} are placeholder variables for the names of the files you want to decompress. You need to replace ${filename1} and ${filename2} with the actual names of the files you want to decompress.

• -ztd is an option flag used with unzstd. It stands for "zero trailers when decompressing". This option instructs unzstd to discard any trailing data when decompressing the files. It is useful when the compressed files might have appended data that is not part of the original data.

• --- is a separator used to indicate the end of command-line options. It ensures that any subsequent arguments are treated as filenames, even if they start with a dash ('-') character. This separator is typically used when filenames could start with a dash or when filenames are read from a file (instead of being directly provided on the command line).

In summary, this command is decompressing two files (filename1 and filename2) using the unzstd command, and while decompressing, it discards any trailing data and treats all subsequent arguments as filenames.