[...]
return [n]
              Causes a function to stop executing and return the value  specified  by  n  to  its
              caller.  If n is omitted, the return status is that of the last command executed in
              the function body.  If return is executed by a trap handler, the last command  used
              to  determine  the status is the last command executed before the trap handler.  If
              return is executed during a DEBUG trap, the last command used to determine the sta-
              tus is the last command executed by the trap handler before return was invoked.  If
              return is used outside a function, but during  execution  of  a  script  by  the  .
              (source)  command, it causes the shell to stop executing that script and return ei-
              ther n or the exit status of the last command executed within  the  script  as  the
              exit status of the script.  If n is supplied, the return value is its least signif-
              icant 8 bits.  The return status is non-zero if return is  supplied  a  non-numeric
              argument,  or  is used outside a function and not during execution of a script by .
              or source.  Any command associated with the RETURN trap is executed  before  execu-
              tion resumes after the function or script.
[...]

return: return [n]
    Visszatér egy függvényből.
    
    Egy függvény vagy egy „source”-olt parancsfájl adott N kilépési kóddal
    való visszatérését okozza. Ha N nincs megadva, az utolsó parancs kilépési
    kódjával tér vissza.
    
    Kilépési kód:
    N-nel tér vissza, kivéve ha nem függvényből vagy parancsfájlból akar
    visszatérni – ekkor sikertelenséget jelez.