mac2unix:tldr:cdac4

The command "mac2unix ${filename}" is used to convert a file from Macintosh line endings format to Unix line endings format.

In Unix-based systems (including Linux and macOS), lines in text files are typically terminated with a newline character ("\n"). However, in Macintosh systems prior to Mac OS X, lines were terminated with a carriage return character ("\r").

So, when you have a file with Macintosh line endings and you want to convert it to Unix line endings, you can use the "mac2unix" command. The "${filename}" is a placeholder for the actual name of the file you want to convert.

By running this command, the "mac2unix" utility will read the file, detect Macintosh line endings, and replace them with Unix line endings. This will modify the file in place, converting it to a format that is more commonly used on Unix-based systems.