Normally, makemap expects the key and data portions of its input file to be separated from each other by linear whitespace (space and tab characters ). The following is an example of such an input file: key data lady relaysite!lady whitespace Beginning with V8.12 sendmail , an alternative to whitespace can be specified on the command line. Consider, for example, an input file (named infile ) that is delimited with commas: key,data To read such an input file with makemap you would run something like the following: % makemap -t, hash outfile < infile The delimiting character that follows the -t must be just a single character. If a multicharacter delimiting character is specified, all but the first character will be silently ignored. If the delimiting character has special meaning to the shell (as does a semicolon), be sure to quote or escape it: -t\; escaped with a backslash -t ';' quoted |