Ubuntu Manpage: gs - Ghostscript (PostScript and PDF language interpreter and previewer)

Provided by: ghostscript_9.26~dfsg+0-0ubuntu0.16.04.14_amd64

NAME

       gs - Ghostscript (PostScript and PDF language interpreter and previewer)

SYNOPSIS

       gs [ options ] [ files ] ...

DESCRIPTION

The gs command invokes Ghostscript, an interpreter of Adobe Systems' PostScript(tm) and Portable Document
Format (PDF) languages. gs reads "files" in sequence and executes them as Ghostscript programs. After
doing this, it reads further input from the standard input stream (normally the keyboard), interpreting
each line separately and output to an output device (may be a file or an X11 window preview, see below).
The interpreter exits gracefully when it encounters the "quit" command (either in a file or from the
keyboard), at end-of-file, or at an interrupt signal (such as Control-C at the keyboard).

The interpreter recognizes many option switches, some of which are described below. Please see the usage
documentation for complete information. Switches may appear anywhere in the command line and apply to all
files thereafter. Invoking Ghostscript with the -h or -? switch produces a message which shows several
useful switches, all the devices known to that executable, and the search path for fonts; on Unix it also
shows the location of detailed documentation.

Ghostscript may be built to use many different output devices. To see which devices your executable
includes, run "gs -h".

Unless you specify a particular device, Ghostscript normally opens the first one of those and directs
output to it.

If you have installed the ghostscript-x Debian package and are under X, the default device is an X11
window (previewer), else ghostscript will use the bbox device and print on stdout the dimension of the
postscript file.

So if the first one in the list is the one you want to use, just issue the command

gs myfile.ps

You can also check the set of available devices from within Ghostscript: invoke Ghostscript and type

devicenames ==

but the first device on the resulting list may not be the default device you determine with "gs -h". To
specify "AbcXyz" as the initial output device, include the switch

-sDEVICE=AbcXyz

For example, for output to an Epson printer you might use the command

gs -sDEVICE=epson myfile.ps

The "-sDEVICE=" switch must precede the first mention of a file to print, and only the switch's first use
has any effect.

Finally, you can specify a default device in the environment variable GS_DEVICE. The order of precedence
for these alternatives from highest to lowest (Ghostscript uses the device defined highest in the list)
is:

Some devices can support different resolutions (densities). To specify the resolution on such a printer,
use the "-r" switch:

gs -sDEVICE=<device> -r<xres>x<yres>

For example, on a 9-pin Epson-compatible printer, you get the lowest-density (fastest) mode with

gs -sDEVICE=epson -r60x72

and the highest-density (best output quality) mode with

gs -sDEVICE=epson -r240x72.

If you select a printer as the output device, Ghostscript also allows you to choose where Ghostscript
sends the output -- on Unix systems, usually to a temporary file. To send the output to a file
"foo.xyz", use the switch

-sOutputFile=foo.xyz

You might want to print each page separately. To do this, send the output to a series of files
"foo1.xyz, foo2.xyz, ..." using the "-sOutputFile=" switch with "%d" in a filename template:

-sOutputFile=foo%d.xyz

Each resulting file receives one page of output, and the files are numbered in sequence. "%d" is a
printf format specification; you can also use a variant like "%02d".

You can also send output to a pipe. For example, to pipe output to the "lpr" command (which, on many
Unix systems, directs it to a printer), use the option

-sOutputFile=%pipe%lpr

You can also send output to standard output:

-sOutputFile=-
or
-sOutputFile=%stdout%

In this case you must also use the -q switch, to prevent Ghostscript from writing messages to standard
output.

To select a specific paper size, use the command line switch

-sPAPERSIZE=<paper_size>

for instance

-sPAPERSIZE=a4
or
-sPAPERSIZE=legal

Most ISO and US paper sizes are recognized. See the usage documentation for a full list, or the
definitions in the initialization file "gs_statd.ps".

Ghostscript can do many things other than print or view PostScript and PDF files. For example, if you
want to know the bounding box of a PostScript (or EPS) file, Ghostscript provides a special "device" that
just prints out this information.

For example, using one of the example files distributed with Ghostscript,

gs -sDEVICE=bbox golfer.ps

prints out

%%BoundingBox: 0 25 583 732
%%HiResBoundingBox: 0.808497 25.009496 582.994503 731.809445

OPTIONS

-- filename arg1 ...
Takes the next argument as a file name as usual, but takes all remaining arguments (even if they
have the syntactic form of switches) and defines the name "ARGUMENTS" in "userdict" (not
"systemdict") as an array of those strings, before running the file. When Ghostscript finishes
executing the file, it exits back to the shell.

-Dname=token
-dname=token
Define a name in "systemdict" with the given definition. The token must be exactly one token (as
defined by the "token" operator) and may contain no whitespace.

-Dname
-dname Define a name in "systemdict" with value=null.

-Sname=string
-sname=string
Define a name in "systemdict" with a given string as value. This is different from -d. For
example, -dname=35 is equivalent to the program fragment
/name 35 def
whereas -sname=35 is equivalent to
/name (35) def

-P Makes Ghostscript to look first in the current directory for library files. By default,
Ghostscript no longer looks in the current directory, unless, of course, the first explicitly
supplied directory is "." in -I. See also the INITIALIZATION FILES section below, and bundled
Use.htm for detailed discussion on search paths and how Ghostcript finds files.

-q Quiet startup: suppress normal startup messages, and also do the equivalent of -dQUIET.

-gnumber1xnumber2
Equivalent to -dDEVICEWIDTH=number1 and -dDEVICEHEIGHT=number2. This is for the benefit of
devices (such as X11 windows) that require (or allow) width and height to be specified.

-rnumber
-rnumber1xnumber2
Equivalent to -dDEVICEXRESOLUTION=number1 and -dDEVICEYRESOLUTION=number2. This is for the
benefit of devices such as printers that support multiple X and Y resolutions. If only one number
is given, it is used for both X and Y resolutions.

-Idirectories
Adds the designated list of directories at the head of the search path for library files.

- This is not really a switch, but indicates to Ghostscript that standard input is coming from a
file or a pipe and not interactively from the command line. Ghostscript reads from standard input
until it reaches end-of-file, executing it like any other file, and then continues with processing
the command line. When the command line has been entirely processed, Ghostscript exits rather
than going into its interactive mode.

Note that the normal initialization file "gs_init.ps" makes "systemdict" read-only, so the values of
names defined with -D, -d, -S, or -s cannot be changed (although, of course, they can be superseded by
definitions in "userdict" or other dictionaries.)

SPECIAL NAMES

-dNOCACHE
Disables character caching. Useful only for debugging.

-dNOBIND
Disables the "bind" operator. Useful only for debugging.

-dNODISPLAY
Suppresses the normal initialization of the output device. This may be useful when debugging.

-dNOPAUSE
Disables the prompt and pause at the end of each page. This may be desirable for applications
where another program is driving Ghostscript.

-dNOPLATFONTS
Disables the use of fonts supplied by the underlying platform (for instance X Windows). This may
be needed if the platform fonts look undesirably different from the scalable fonts.

-dSAFER
Restricts file operations the job can perform. Strongly recommended for spoolers, conversion
scripts or other sensitive environments where a badly written or malicious PostScript program code
must be prevented from changing important files.

-dWRITESYSTEMDICT
Leaves "systemdict" writable. This is necessary when running special utility programs, but is
strongly discouraged as it bypasses normal Postscript security measures.

-sDEVICE=device
Selects an alternate initial output device, as described above.

-sOutputFile=filename
Selects an alternate output file (or pipe) for the initial output device, as described above.

SAFER MODE

The -dSAFER option disables the "deletefile" and "renamefile" operators and prohibits opening piped
commands ("%pipe%cmd"). Only "%stdout" and "%stderr" can be opened for writing. It also disables reading
from files, except for "%stdin", files given as a command line argument, and files contained in paths
given by LIBPATH and FONTPATH or specified by the system params /FontResourceDir and /GenericResourceDir.

This mode also sets the .LockSafetyParams parameter of the initial output device to protect against
programs that attempt to write to files using the OutputFile device parameter. Since the device
parameters specified on the command line, including OutputFile, are set prior to SAFER mode, use of
"-sOutputFile=..." on the command line is unrestricted.

SAFER mode prevents changing the /GenericResourceDir, /FontResourceDir, /SystemParamsPassword, and
/StartJobPassword.

While SAFER mode is not the default, it is the default for many wrapper scripts such as ps2pdf and may be
the default in a subsequent release of Ghostscript. Thus when running programs that need to open files
or set restricted parameters you should pass the -dNOSAFER command line option or its synonym
-dDELAYSAFER.

When running with -dNOSAFER it is possible to perform a "save" followed by ".setsafe", execute a file or
procedure in SAFER mode, and then use "restore" to return to NOSAFER mode. In order to prevent the save
object from being restored by the foreign file or procedure, the ".runandhide" operator should be used to
hide the save object from the restricted procedure.

FILES

       The  locations of many Ghostscript run-time files are compiled into the executable when it is built.  Run
       "gs -h" to find the location of Ghostscript documentation on your system, from which  you  can  get  more
       details. On a Debian system they are in /usr.

       /usr/share/ghostscript/[0-9]*.[0.9]*/*
              Startup  files,  utilities,  and  basic  font  definitions (where [0-9]*.[0.9]* is the ghostscript
              version)

       /usr/share/fonts/type1/gsfonts/*
              More font definitions from the gsfonts package

       /usr/share/doc/ghostscript/examples/*
              Ghostscript demonstration files (if ghostscript-doc package is installed)

       /usr/share/doc/ghostscript/*
              Diverse document files (may need to install ghostscript-doc package)

INITIALIZATION FILES

       When looking for the initialization files "gs_*.ps", the files related to fonts,  or  the  file  for  the
       "run"  operator,  Ghostscript  first  tries  to  open  the file with the name as given, using the current
       working directory if no directory is specified.  If this fails, and the  file  name  doesn't  specify  an
       explicit  directory  or  drive  (for  instance,  doesn't  contain "/" on Unix systems), Ghostscript tries
       directories in this order:

       1.  the directories specified by the -I switches in the command line (see below), if any;

       2.  the directories specified by the GS_LIB environment variable, if any;

       3.  the directories specified by the GS_LIB_DEFAULT macro in the Ghostscript makefile when the executable
           was  built.   GS_LIB_DEFAULT  is  "/usr/share/ghostscript/[0-9]*.[0-9]*/lib" on a Debian system where
           "[0-9]*.[0-9]*" represents the Ghostscript version number

       Each of these (GS_LIB_DEFAULT, GS_LIB, and -I parameter) may be either a single directory or  a  list  of
       directories separated by ":".

ENVIRONMENT

       GS_OPTIONS
              String of options to be processed before the command line options

       GS_DEVICE
              Used to specify an output device

       GS_FONTPATH
              Path names used to search for fonts

       GS_LIB Path names for initialization files and fonts

       TEMP   Where temporary files are made

X RESOURCES

       Ghostscript, or more properly the X11 display device, looks for the following resources under the program
       name "Ghostscript":

       borderWidth
              The border width in pixels (default = 1).

       borderColor
              The name of the border color (default = black).

       geometry
              The window size and placement, WxH+X+Y (default is NULL).

       xResolution
              The number of x pixels per inch (default is computed from WidthOfScreen and WidthMMOfScreen).

       yResolution
              The number of y pixels per inch (default is computed from HeightOfScreen and HeightMMOfScreen).

       useBackingPixmap
              Determines whether backing store is to be used for saving display window (default = true).

       See the usage document for a more complete list of resources.  To set these resources on Unix,  put  them
       in a file such as "~/.Xresources" in the following form:

            Ghostscript*geometry:     612x792-0+0
            Ghostscript*xResolution: 72
            Ghostscript*yResolution: 72

       Then merge these resources into the X server's resource database:

            % xrdb -merge ~/.Xresources

BUGS

       See http://bugs.ghostscript.com/ and the Usenet news group comp.lang.postscript.

VERSION

       This document was last revised for Ghostscript version 9.26.

AUTHOR

       Artifex Software, Inc.  are  the  primary  maintainers  of  Ghostscript.   Russell  J.  Lang,  gsview  at
       ghostgum.com.au, is the author of most of the MS Windows code in Ghostscript.