In each case, it forks a child to handle the request so the parent can continue to listen for more requests. The -l flag causes lpd to log valid requests received from the network. This can be useful for debugging purposes.
Access control is provided by two means.
Second, if the rs capability is specified in the printcap entry for the printer being accessed, lpr requests will only be honored for those users with accounts on the machine with the printer. The file minfree in each spool directory contains the number of disk blocks to leave free so that the line printer queue won't completely fill the disk. The minfree file can be edited with your favorite text editor. Lines in each cf file specify files to be printed or non-printing actions to be performed. Each such line begins with a key character to specify what to do with the remainder of the line.