# troff(1) - man - phpMan [TROFF(1)](https://www.chedong.com/phpMan.php/man/TROFF/1/markdown) General Commands Manual [TROFF(1)](https://www.chedong.com/phpMan.php/man/TROFF/1/markdown) ## NAME troff - the troff processor of the groff text formatting system ## SYNOPSIS **troff** [**-abcivzCERU**] [**-d** _cs_] [**-f** _fam_] [**-F** _dir_] [**-I** _dir_] [**-m** _name_] [**-M** _dir_] [**-n** _num_] [**-o** _list_] [**-r** _cn_] [**-T** _name_] [**-w** _name_] [**-W** _name_] [_file_ ...] ## DESCRIPTION This manual page describes the GNU version of **troff**. It is part of the groff document for‐ matting system. It is functionally compatible with Unix troff, but has many extensions, see **groff**___**[diff**(7)](https://www.chedong.com/phpMan.php/man/diff/7/markdown). Usually it should be invoked using the [**groff**(1)](https://www.chedong.com/phpMan.php/man/groff/1/markdown) command which will also run preprocessors and postprocessors in the appropriate order and with the appropriate options. ## OPTIONS Whitespace is permitted between a command-line option and its argument. ### -a ### -b track down the cause of the error. The line numbers given in the backtrace may not always be correct, for **troff**'s idea of line numbers gets confused by **as** or **am** re‐ quests. ### -c ### -C ### -d ### -d Define _c_ or _name_ to be a string _s_; _c_ must be a one letter name. ### -E standard error by macro packages using the **tm** or **tm1** requests. ### -f ### -F name of the device) and there for the _DESC_ file and font files. _dir_ is scanned before all other font directories. ### -i ### -I the command line and those named in **.psbb** requests). The search path is initialized with the current directory. This option may be specified more than once; the directo‐ ries are then searched in the order specified (but before the current directory). If you want to make the current directory be read before other directories, add **-I.** at the appropriate place. No directory search is performed for files with an absolute file name. ### -m first searched for in directories given with the **-M** command-line option, then in di‐ rectories given in the _GROFF_TMAC_PATH_ environment variable, then in the current di‐ rectory (only if in unsafe mode), the home directory, _/usr/lib/groff/site-tmac_, _/usr/_ _share/groff/site-tmac_, and _/usr/share/groff/1.22.4/tmac_. ### -M other macro directories. ### -n ### -o print page _n_, _m_**-**_n_ means print every page between _m_ and _n_, **-**_n_ means print every page up to _n_, _n_**-** means print every page from _n_. **troff** will exit after printing the last page in the list. ### -r ### -r Set number register _c_ or _name_ to _n_; _c_ must be a one character name; _n_ can be any troff numeric expression. ### -R ### -T detailed description. ### -U For security reasons, these potentially dangerous requests are disabled otherwise. It will also add the current directory to the macro search path. ### -v ### -w To enable most useful warnings use **-w** **all**. To enable absolutely all warnings use **-w** **w** instead. Multiple **-w** options are allowed. ### -W -W ### -z ## WARNINGS The warnings that can be given by **troff** are divided into the following categories. The name associated with each warning is used by the **-w** and **-W** options; the number is used by the **warn** request, and by the **.warn** register; it is always a power of 2 to allow bitwise composition. ┌─────────────────────┬─────────────────────────────┐ │Bit Code Warning │ Bit Code Warning │ ├─────────────────────┼─────────────────────────────┤ │ 0 _1_ **char** │ 10 _1024_ **reg** │ │ 1 _2_ **number** │ 11 _2048_ **tab** │ │ 2 _4_ **break** │ 12 _4096_ **right-brace** │ │ 3 _8_ **delim** │ 13 _8192_ **missing** │ │ 4 _16_ **el** │ 14 _16384_ **input** │ │ 5 _32_ **scale** │ 15 _32768_ **escape** │ │ 6 _64_ **range** │ 16 _65536_ **space** │ │ 7 _128_ **syntax** │ 17 _131072_ **font** │ │ 8 _256_ **di** │ 18 _262144_ **ig** │ │ 9 _512_ **mac** │ 19 _524288_ **color** │ │ │ 20 _1048576_ **file** │ └─────────────────────┴─────────────────────────────┘ **break** 4 In fill mode, lines which could not be broken so that their length was less than the line length. This is enabled by default. **char** 1 Non-existent characters. This is enabled by default. **color** 524288 Color-related warnings. **delim** 8 Missing or mismatched closing delimiters. **di** 256 Use of **di** or **da** without an argument when there is no current diversion. **el** 16 Use of the **el** request with no matching **ie** request. **escape** 32768 Unrecognized escape sequences. When an unrecognized escape sequence is encountered, the escape character is ignored. **file** 1048576 Indicates a missing file for the **mso** request. Enabled by default. **font** 131072 Non-existent fonts. This is enabled by default. **ig** 262144 Invalid escapes in text ignored with the **ig** request. These are condi‐ tions that are errors when they do not occur in ignored text. **input** 16384 Invalid input characters. **mac** 512 Use of undefined strings, macros and diversions. When an undefined string, macro or diversion is used, that string is automatically defined as empty. So, in most cases, at most one warning will be given for each name. **missing** 8192 Requests that are missing non-optional arguments. **number** 2 Invalid numeric expressions. This is enabled by default. **range** 64 Out of range arguments. **reg** 1024 Use of undefined number registers. When an undefined number register is used, that register is automatically defined to have a value of 0. So, in most cases, at most one warning will be given for use of a particular name. **right-brace** 4096 Use of **\}** where a number was expected. **scale** 32 Meaningless scaling indicators. **space** 65536 Missing space between a request or macro and its argument. This warning will be given when an undefined name longer than two characters is en‐ countered, and the first two characters of the name make a defined name. The request or macro will not be invoked. When this warning is given, no macro is automatically defined. This is enabled by default. This warn‐ ing will never occur in compatibility mode. **syntax** 128 Dubious syntax in numeric expressions. **tab** 2048 Inappropriate use of a tab character. Either use of a tab character where a number was expected, or use of tab character in an unquoted macro argument. There are also names that can be used to refer to groups of warnings: **all** All warnings except **di**, **mac**, and **reg**. It is intended that this covers all warnings that are useful with traditional macro packages. **w** All warnings. ## ENVIRONMENT _GROFF_TMAC_PATH_ A colon separated list of directories in which to search for macro files. **troff** will scan directories given in the **-M** option before these, and in standard directories (current directory if in unsafe mode, home directory, _/usr/lib/groff/site-tmac_, _/usr/_ _share/groff/site-tmac_, _/usr/share/groff/1.22.4/tmac_) after these. _GROFF_TYPESETTER_ Default device. _GROFF_FONT_PATH_ A colon separated list of directories in which to search for the _dev_name directory. **troff** will scan directories given in the **-F** option before these, and in standard di‐ rectories (_/usr/share/groff/site-font_, _/usr/share/groff/1.22.4/font_, _/usr/lib/font_) after these. ## FILES _/usr/share/groff/1.22.4/tmac/troffrc_ Initialization file (called before any other macro package). _/usr/share/groff/1.22.4/tmac/troffrc-end_ Initialization file (called after any other macro package). _/usr/share/groff/1.22.4/tmac/_name_.tmac_ _/usr/share/groff/1.22.4/tmac/tmac._name Macro files _/usr/share/groff/1.22.4/font/dev_name_/DESC_ Device description file for device _name_. _/usr/share/groff/1.22.4/font/dev_name_/_F Font file for font _F_ of device _name_. Note that _troffrc_ and _troffrc-end_ are searched for neither in the current nor the home direc‐ tory by default for security reasons (even if the **-U** option is given). Use the **-M** command- line option or the _GROFF_TMAC_PATH_ environment variable to add these directories to the search path if necessary. ## AUTHORS The GNU version of _troff_ was originally written by James Clark; he also wrote the original version of this document, which was modified by Werner Lemberg ⟨⟩ and Bernd Warken ⟨⟩. ## SEE ALSO [**groff**(1)](https://www.chedong.com/phpMan.php/man/groff/1/markdown) The main program of the _groff_ system, a wrapper around _troff_. [**groff**(7)](https://www.chedong.com/phpMan.php/man/groff/7/markdown) A description of the _groff_ language, including a short but complete reference of all predefined requests, registers, and escapes of plain _groff_. From the command line, this is called by **man** **7** **groff** **groff**___**[diff**(7)](https://www.chedong.com/phpMan.php/man/diff/7/markdown) The differences of the _groff_ language and the _classical_ _troff_ language. Currently, this is the most actual document of the _groff_ system. [**roff**(7)](https://www.chedong.com/phpMan.php/man/roff/7/markdown) An overview over _groff_ and other _roff_ systems, including pointers to further related documentation. _Groff:_ _The_ _GNU_ _Implementation_ _of_ _troff_, by Trent A. Fisher and Werner Lemberg, is the primary _groff_ manual. You can browse it interactively with “info groff”. groff 1.22.4 23 March 2022 [TROFF(1)](https://www.chedong.com/phpMan.php/man/TROFF/1/markdown)