man pages for gs
6.0 Last change: 3 February 2000
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) languages. gs reads
"files" in sequence and executes them as Ghostscript pro-
grams. After doing this, it reads further input from the
standard input stream (normally the keyboard), interpreting
each line separately. The interpreter quits 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 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 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:
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= -rx
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".
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 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=a_known_paper_size
for instance
-sPAPERSIZE=a4
or
-sPAPERSIZE=legal
At this time, the known paper sizes, defined in the initial-
ization file "gs_statd.ps", are: tab(>); l l l l l.
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 hal-
fletter>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 infor-
mation:
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
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 or "\" on DOS systems),
Ghostscript tries directories in this order:
1. the directories specified by the -I switches in the com-
mand 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 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 ":".
X RESOURCES
Ghostscript looks for the following resources under the pro-
gram 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 sav-
ing 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 "ARGU-
MENTS" 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 defini-
tion. 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
-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
-dDISKFONTS
Causes individual character outlines to be loaded from
the disk the first time they are encountered. (Nor-
mally 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 debug-
ging.
-dNODISPLAY
Suppresses the normal initialization of the output dev-
ice. 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
Disables the "deletefile" and "renamefile" operators
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 mali-
cious PostScript program must be prevented from chang-
ing 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 ini-
tial 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 different
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 definitions
/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 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
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 6.0.
AUTHOR
L. Peter Deutsch is the principal author
of Ghostscript. Russell J. Lang is the
author of most of the MS Windows code in Ghostscript.