gs
GS(1) Ghostscript GS(1)
NAME
gs - Ghostscript (PostScript and PDF language interpreter
and previewer)
SYNOPSIS
gs [ options ] [ files ] ... (Unix, VMS)
gswin32 [ options ] [ files ] ... (MS Windows)
gswin32c [ options ] [ files ] ... (MS Windows)
gs386 [ options ] [ files ] ... (DOS for PC)
gsos2 [ options ] [ files ] ... (OS/2)
DESCRIPTION
The gs (gswin32, gswin32c, gs386, gsos2) command invokes
Ghostscript, an interpreter of Adobe Systems'
PostScript(tm) and Portable Document Format (PDF) lan
guages. 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 key
board), interpreting each line separately. The inter
preter quits gracefully when it encounters the "quit" com
mand (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 several switches described
below, which 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 able to use many different output
devices. To see which devices your executable can use,
run "gs -h". Unless you specify a particular device,
Ghostscript normally opens the first one of those and
directs output to it, 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. Alternatively, in Ghostscript you can type
(epson) selectdevice
(myfile.ps) run
All output then goes to the printer until you select
another device with the "selectdevice" procedure in the
PostScript program stream, for example
(vga) selectdevice
or
(x11) selectdevice
Finally, you can specify a default device in the environ
ment variable GS_DEVICE. The order of precedence for
these alternatives from highest to lowest (Ghostscript
uses the device defined highest in the list) is:
selectdevice
(command line)
GS_DEVICE
(first device in build list)
Some printers can print at different resolutions (densi
ties). 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 out
put -- 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 file
name 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".
On Unix systems 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
switch
-sOutputFile=\|lpr
You can also send output to standard output for piping
with the switch
-sOutputFile=-
In this case 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=a_known_paper_size
for instance
-sPAPERSIZE=a4
or
-sPAPERSIZE=legal
At this time, the known paper sizes, defined in the ini
tialization file "gs_statd.ps", are:
PAPERSIZE X inches Y inches X cm Y cm
-----------------------------------------------------
a0 33.0556 46.7778 83.9611 118.816
a1 23.3889 33.0556 59.4078 83.9611
a2 16.5278 23.3889 41.9806 59.4078
a3 11.6944 16.5278 29.7039 41.9806
a4 8.26389 11.6944 20.9903 29.7039
a5 5.84722 8.26389 14.8519 20.9903
a6 4.125 5.84722 10.4775 14.8519
a7 2.91667 4.125 7.40833 10.4775
a8 2.05556 2.91667 5.22111 7.40833
a9 1.45833 2.05556 3.70417 5.22111
a10 1.02778 1.45833 2.61056 3.70417
b0 39.3889 55.6667 100.048 141.393
b1 27.8333 39.3889 70.6967 100.048
b2 19.6944 27.8333 50.0239 70.6967
b3 13.9167 19.6944 35.3483 50.0239
b4 9.84722 13.9167 25.0119 35.3483
b5 6.95833 9.84722 17.6742 25.0119
archA 9 12 22.86 30.48
archB 12 18 30.48 45.72
archC 18 24 45.72 60.96
archD 24 36 60.96 91.44
archE 36 48 91.44 121.92
flsa 8.5 13 21.59 33.02
flse 8.5 13 21.59 33.02
halfletter 5.5 8.5 13.97 21.59
note 7.5 10 19.05 25.4
letter 8.5 11 21.59 27.94
legal 8.5 14 21.59 35.56
11x17 11 17 27.94 43.18
ledger 17 11 43.18 27.94
Note that the B paper sizes are ISO sizes: for information
about using JIS B sizes, see Use.htm.
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:
gs -sDEVICE=bbox myfile.ps
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
INITIALIZATIONFILES
When looking for the initialization files "gs_*.ps", the
files related to fonts, or the file for the "run" opera
tor, 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 or "\" on
DOS 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. When gs is built on Unix, GS_LIB_DEFAULT is
usually
"/usr/local/share/ghostscript/#.##:/usr/local/share/ghostscript/fonts"
where "#.##" represents the Ghostscript version num
ber.
Each of these (GS_LIB_DEFAULT, GS_LIB, and -I parameter)
may be either a single directory or a list of directories
separated by ":".
X RESOURCES
Ghostscript 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 com
puted from WidthOfScreen and WidthMMOfScreen).
yResolution
The number of y pixels per inch (default is com
puted 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
SWITCHES
-- 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 "system
dict") 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 defi
nition. 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
-q Quiet startup: suppress normal startup messages,
and also do the equivalent of -dQUIET.
-gnumber1xnumber2
Equivalent to -dDEVICEWIDTH=number1 and -dDEVICE
HEIGHT=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 -dDE
VICEYRESOLUTION=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 com
mand 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 defini
tions 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 out
lines when it loads a font.) This may allow load
ing more fonts into RAM, at the expense of slower
rendering.
-dNOCACHE
Disables character caching. Useful only for debug
ging.
-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 underly
ing platform (for instance X Windows). This may be
needed if the platform fonts look undesirably dif
ferent from the scalable fonts.
-dSAFER
Disables the "deletefile" and "renamefile" opera
tors and the ability to open files in any mode
other than read-only. This may be desirable for
spoolers or other sensitive environments where a
badly written or malicious PostScript program must
be prevented from changing important files.
-dWRITESYSTEMDICT
Leaves "systemdict" writable. This is necessary
when running special utility programs such as
font2c and pcharstr, which must bypass normal
PostScript access protection.
-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.
FILES
The locations of many Ghostscript run-time files are com
piled into the executable when it is built. On Unix these
are typically based in /usr/local, but this may be differ
ent on your system. Under DOS they are typically based in
C:\GS, but may be elsewhere, especially if you install
Ghostscript with GSview. Run "gs -h" to find the location
of Ghostscript documentation on your system, from which
you can get more details.
/usr/local/share/ghostscript/#.##/*
Startup files, utilities, and basic font defini
tions
/usr/local/share/ghostscript/fonts/*
More font definitions
/usr/local/share/ghostscript/#.##/examples/*
Ghostscript demonstration files
/usr/local/share/ghostscript/#.##/doc/*
Diverse document files
ENVIRONMENT
GS_OPTIONS
String of options to be processed before the com
mand 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
SEE ALSO
The various Ghostscript document files (above), especially
Use.htm.
BUGS
See the Usenet news group comp.lang.postscript.
VERSION
This document was last revised for Ghostscript version
6.50.
AUTHOR
L. Peter Deutsch <ghost@aladdin.com> is the principal
author of Ghostscript. Russell J. Lang <rjl@aladdin.com>
is the author of most of the MS Windows code in
Ghostscript.
6.50 2 December 2000 GS(1)