addftinfo reads a troff font file and adds some additional font-metric information that is used by the groff system. afmtodit creates a font file for use with groff and grops. eqn compiles descriptions of equations embedded within troff input files into commands that are understood by troff. eqn2graph converts an EQN equation into a cropped image. grn is a groff preprocessor for gremlin files. grodvi is a driver for groff that produces TeX dvi format. groff is a front-end to the groff document formatting system. Normally it runs the troff program and a post-processor appropriate for the selected device. groffer displays groff files and man pages on X and tty. grog reads files and guesses which of the groff options -e, -man, -me, -mm, -ms, -p, -s, and -t are required for printing files, and reports the groff command including those options. grolbp is a groff driver for Canon CAPSL printers (LBP-4 and LBP-8 series laser printers). grolj4 is a driver for groff that produces output in PCL5 format suitable for an HP Laserjet 4 printer. grops translates the output of GNU troff to Postscript. grotty translates the output of GNU troff into a form suitable for typewriter-like devices. gtbl is the GNU implementation of tbl. hpftodit creates a font file for use with groff -Tlj4 from an HP-tagged font metric file. indxbib makes an inverted index for the bibliographic databases a specified file for use with refer, lookbib, and lkbib. lkbib searches bibliographic databases for references that contain specified keys and reports any references found. lookbib prints a prompt on the standard error (unless the standard input is not a terminal), reads from the standard input a line containing a set of keywords, searches the bibliographic databases in a specified file for references containing those keywords, prints any references found on the standard output and repeats this process until the end of input. mmroff is a simple preprocessor for groff. neqn formats equations for ascii output. nroff is a script that emulates the nroff command using groff. pfbtops translates a Postscript font in .pfb format to ASCII. pic compiles descriptions of pictures embedded within troff or TeX input files into commands understood by TeX or troff. pic2graph converts a PIC diagram into a cropped image. pre-grohtml translates the output of GNU troff to html. post-grohtml translates the output of GNU troff to html. refer copies the contents of a file to the standard output, except that lines between .[ and .] are interpreted as citations, and lines between .R1 and .R2 are interpreted as commands about how citations are to be processed. soelim reads files and replaces lines of the form .so file by the contents of the mentioned file. tbl compiles descriptions of tables embedded within troff input files into commands that are understood by troff. tfmtodit creates a font file for use with groff -Tdvi. troff is highly compatible with Unix troff. Usually it should be invoked using the groff command, which will also run preprocessors and post-processors in the appropriate order and with the appropriate options. zsoelim is the GNU implementation of soelim.