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
programs. 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 (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".
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 initialization
file "gs_statd.ps", are:
l l l l l.
.sp
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,
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 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 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 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:
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 "systemdict") as an
array of those strings, before running the file. When Ghostscript
finishes executing the file, it exits back to the shell.
-D name = token
-d name = 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.
-D name
-d name Define a name in "systemdict" with value=null.
-S name = string
-s name = 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.
-g number1 x number2
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.
-r number
-r number1 x number2 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.
-I directories
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
-dSAFER
Disables the "deletefile" and "renamefile" operators and the ability to
open files in any mode other than read-only. This is desirable for
spoolers or any other environments where a malicious or badly written
PostScript program must be prevented from changing important files.
-dBATCH
Causes Ghostscript to exit after processing all files named on the
command line, rather than prompting for further PostScript
commands.
-dNOPAUSE
Disables the prompt and pause at the end of each page. This may be
desirable in converting documents or for applications where another
program is driving Ghostscript.
-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.
-dNODISPLAY
Suppresses the normal initialization of the output device.
This may be useful when debugging.
-dNOCACHE
Disables character caching. Useful only for debugging.
-dNOBIND
Disables the "bind" operator. Useful only for debugging.
-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.
-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.
-dWRITESYSTEMDICT
Leaves "systemdict" writable. This is necessary when running special
utility programs such as font2c and pcharstr, which must bypass
normal PostScript access protection.
FILES
The locations of many Ghostscript run-time files are compiled 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 7.07.
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.
