GS(1) Ghostscript GS(1)NAME
gs - Ghostscript (PostScript and PDF language interpreter and pre‐
viewer)
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 (nor‐
mally 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 infor‐
mation. 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 Ghost‐
script: 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 "-sOut‐
putFile=" switch with "%d" in a filename template:
-sOutputFile=foo%d.xyz
Each resulting file receives one page of output, and the files are num‐
bered 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 Ghost‐
script,
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" oper‐
ator) 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 sup‐
plied 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 -dDEVICEYRESOLU‐
TION=number2. This is for the benefit of devices such as print‐
ers that support multiple X and Y resolutions. If only one num‐
ber 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 interac‐
tively 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 "system‐
dict" 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 defi‐
nitions in "userdict" or other dictionaries.)
SPECIAL NAMES-dDISKFONTS
Causes individual character outlines to be loaded from the disk
the first time they are encountered. (Normally Ghostscript
loads all the character outlines when it loads a font.) This
may allow loading more fonts into RAM, at the expense of slower
rendering.
-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 recom‐
mended for spoolers, conversion scripts or other sensitive envi‐
ronments 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 out‐
put 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 out‐
put 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 unre‐
stricted.
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 Ghost‐
script 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 dis‐
play 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
SEE ALSO
The various Ghostscript document files (above), especially Use.htm. On
Debian you may need to install ghostscript-doc before reading the docu‐
mentation.
BUGS
See http://bugs.ghostscript.com/ and the Usenet news group
comp.lang.postscript.
VERSION
This document was last revised for Ghostscript version 9.22.
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.
9.22 4 October 2017 GS(1)
