Once upon a time, if you were an avid user of bc(1) you where an avid user of dc(1). This is an extract of the Unix V7 man page for bc(1) https://man.cat-v.org

Once upon a time, if you were an avid user of bc(1) you where an avid user of dc(1). This is an extract of the Unix V7 man page for bc(1) https://man.cat-v.org/unix_7th/1/bc https://man.cat-v.org/unix_7th/1/bc : Bc is actually a preprocessor for dc(1), which it invokes automatically, unless the -c (compile only) option is pre- sent. In this case the dc input is sent to the standard output instead.