.TH TAC 1L "GNU Text Utilities" "FSF" \" -*- nroff -*- .SH NAME tac \- concatenate and print files in reverse .SH SYNOPSIS .B tac [\-br] [\-s separator] [\-\-before] [\-\-regex] [\-\-separator=separator] [\-\-help] [\-\-version] [file...] .SH DESCRIPTION This manual page documents the GNU version of .BR tac . .B tac copies each given file, or the standard input if none are given or when a file name of `-' is encountered, to the standard output with the order of the records reversed. The records are separated by instances of a string, or a newline if none is given. By default, the separator string is attached to the end of the record that it follows in the file. .SS OPTIONS .TP .I "\-b, \-\-before" The separator is attached to the beginning of the record that it precedes in the file. .TP .I "\-r, \-\-regex" The separator is a regular expression. .TP .I "\-s, \-\-separator separator" Use .I separator as the record separator. .TP .I "\-\-help" Print a usage message and exit with a non-zero status. .TP .I "\-\-version" Print version information on standard error then exit.