Explorer - Mosaic & Web/Explorer - Mosaic & Web.iso/helpers/ghostvew/gvpm.inf

OS/2 Help File | 1994-08-03 | 35.2 KB | 981 lines

ΓòÉΓòÉΓòÉ 1. Overview ΓòÉΓòÉΓòÉ

PM GSview is a graphical interface for OS/2 Ghostscript. Ghostscript is an
interpreter for the PostScript page description language used by laser
printers. For documents following the Adobe PostScript Document Structuring
Conventions, GSview allows selected pages to be viewed or printed. GSview can
be used with Ghostscript 3.0 or later. GSview was inspired by Tim Theisen's X11
Ghostview program.

Installation
Document Structuring Conventions
Opening a Document
Page Selection
Zoom
Document Information
Printing
Text Extract and Find
Clipboard
Options
Page Orientation
Page Size and Display Resolution
Keys
Command line options
Copyright
Common Problems
Internals


ΓòÉΓòÉΓòÉ 2. Installation ΓòÉΓòÉΓòÉ

First you need to install Ghostscript 3.0. This version of GSview will not work
with earlier versions of Ghostscript.

Next install PM GSview by copying gvpm.exe and gvpm.hlp to your Ghostscript
directory.

Start GSview then select Options | Ghostscript Command, and enter the correct
executable path and include path for Ghostscript. For example

  c:\gs\gsos2.exe -Ic:\gs;c:\psfonts

It is essential that you get both the executable and the include path correct
otherwise GSview will either complain that it cannot run gsos2, or it will
start and then immediately exit with an error code.

Set the environment variable TEMP to point to a directory for temporary files.
For example:

  SET TEMP=c:\temp

The directory must exist and must be writeable.

If you have some Type 1 fonts on your system, it may be possible to tell
Ghostscript to use them.  See Fontmap.os2 and Fontmap.atm supplied with
Ghostscript for examples.

If you have problems, try reading the help topic Common Problems.

To uninstall GSview, remove the files you installed above, then remove
c:\os2\gvpm.ini from the appropriate system directory.


ΓòÉΓòÉΓòÉ 3. Document Structuring Conventions ΓòÉΓòÉΓòÉ

  Adobe has defined a set of extended comment conventions that provide
additional information about the page structure and resource requirements of a
PostScript file. If a file contains these Document Structuring Convention (DSC)
comments, GSview can display pages in random order using Goto Page and display
pages in reverse order using Previous Page.  Selected pages can be extracted to
another file or printed.

If a file does not contain DSC comments, GSview can only display the pages in
the original order.

DSC conforming files start with the comment line:

 %!PS-Adobe-3.0

where the number 3.0 may change and is the DSC version number. Some programs
write PostScript files with a control-D as the first character of the file,
followed by the comment line mentioned above. GSview will correctly report that
these files are not DSC conforming, but will still display them with page
selection features available. Complain to the author of the program that
produced the PostScript file. To make the file DSC conforming, edit it to
remove the control-D character.

DSC conforming files contain lines such as:

 %%Pages: 24
 %%Page: 1 1

These lines tell GSview how many pages a document contains and where they
start.  GSview uses this information to select individual pages.

Encapsulated PostScript Files (EPSF) are single page documents that contain a
subset of the DSC comments and PostScript commands. EPS files start with the
comment line:

 %!PS-Adobe-3.0 EPSF-3.0

EPS files are commonly used for inclusion in other documents and for this
reason require the bounding box comment:

  %%BoundingBox: llx lly urx ury

where llx, lly, urx and ury are integers giving the x and y coordinates of the
lower left and upper right corners of a bounding box which encloses all marks
made on the page.

Some EPS files contain a preview of the PostScript document. This preview can
be a Windows Metafile, a TIFF file, or an Interchange preview (EPSI format).
For the Windows Metafile or TIFF file preview, the EPS file under DOS contains
a binary header which specifies the location and lengths of the preview and
PostScript language sections of the EPS file. For the Interchange format, the
preview is contained in DSC comments starting with

 %%BeginPreview: width height depth lines

An EPS file with a preview can be created from an EPS file without a preview
using Add EPS Preview.


ΓòÉΓòÉΓòÉ 4. Opening a Document ΓòÉΓòÉΓòÉ

  The Open command on the File menu opens a file and displays the first page.

If the file contains DSC comments, pages can be selected using Next Page,
Previous Page and Goto Page.

If the file does not contain DSC comments, Previous Page and Goto Page will not
work.  Another file should not be selected until a last page of the file has
been displayed.

When a file is open, GSview will display the document filename, the current
page (if available) and while the cursor is over the image, the location of the
cursor in coordinates specified by Options | Units.  The coordinate can be
PostScript points (1/72"), millimetres or inches. The cursor location is useful
for calculating bounding boxes.

The Select File command is similar to Open but it does not display the
document. This command is useful for opening a document prior to printing it.

The Close command closes the currently open document. This should be used
before the current file is changed by another program. If you do not do this
and GSview detects that the file length or date have changed, it will close
Ghostscript and rescan the document.

See also Print.


ΓòÉΓòÉΓòÉ 5. Page Selection ΓòÉΓòÉΓòÉ

  Next Page moves to the next page of a document. This works even if the
document does not contain DSC comments.

Previous Page moves to the previous page.

Redisplay redisplays the current page.

Goto Page shows a dialog box which allows selection of the next page number to
display.  The Select Page dialog box shows page labels since these are likely
to be more useful than a sequential page number.

The Previous Page, Redisplay and Goto Page commands work only if the document
contains DSC comments.


ΓòÉΓòÉΓòÉ 6. Zoom ΓòÉΓòÉΓòÉ

To enlarge a displayed feature, position the cross-hair mouse pointer over the
feature then press the right mouse button. The window will swap from normal
display resolution to zoom resolution and the status line will have the word
Zoomed appended to it. The zoomed feature will be in the centre of the window.
To cancel Zoom, press the right mouse button again or select any command that
redraws the page (e.g. Redisplay, Next Page). By default the zoom resolution is
300 dots per inch but this can be changed with the Media | Zoom Resolution
command.

Zoom will only work for DSC conforming documents.


ΓòÉΓòÉΓòÉ 7. Document Information ΓòÉΓòÉΓòÉ

A brief information area at the top of the window is used by GSview to display
the document filename, the current page number and label (if available) and
while the cursor is over the image, the location of the cursor in coordinates
specified by Options | Units. The cursor location is useful for calculating
bounding boxes.

The Info command on the File menu shows a dialog box with the following
information about the DSC comments in the current document.

File is the full pathname to the document.

Type is DSC, EPS, No DSC comments or 'Ignoring DSC Comments'. EPS is an
Encapsulated PostScript File - a single page document that contains a subset of
the DSC comments and PostScript commands. EPS files are commonly used for
inclusion in other documents. Ignoring DSC Comments is displayed if Options |
Ignore DSC is selected.

Title is a text title that can be used when printing banner pages and for
routing or recognising documents.

Date is the time the document was created.

BoundingBox specifies a box that encloses all the marks painted on the page.
The four integer values are the coordinates of the lower left and upper right
corners of the bounding box in default user coordinates (1/72 inch).

Orientation is either Portrait or Landscape.

Default Media gives the media name followed by the width and height of that
media in default user coordinates (1/72 inch).

Page Order is either Ascending, Descending or Special

Pages is the total number of pages in the document.

Page gives the page label and page number.

Bitmap is the size of the display bitmap in pixels which may be useful if you
are copying the displayed image to the clipboard.


ΓòÉΓòÉΓòÉ 8. Printing ΓòÉΓòÉΓòÉ

  The Print command on the File menu allows printing of the document using
Ghostscript. The Ghostscript printer driver and resolution are selected using
the Select Device dialog box.  Pages are selected using the Select Pages dialog
box.  The All, Odd and Even buttons provide quick selection of pages.

This list of available devices and resolutions is stored in the [Devices]
section of gvpm.ini. The default list of devices and resolutions is taken from
the standard distribution version of Ghostscript 3.0 and may not be complete.

To print a document without displaying it, open the document using Select File.

Print To File is similar to the Print command except that Ghostscript will
write the output to a file instead of sending it to a printer.

If you want to produce a bitmap, some useful drivers are bmpmono, bmp16, bmp16m
and bmp256.

Print File sends a file to a local port, bypassing the Presentation Manager
printer drivers. This is useful for sending a document to a PostScript printer,
or for sending an output file produced by Ghostscript to a printer.

Extract allows a range of pages to be copied from the current document to a new
document.  For example, ten pages can be extracted from the middle of the
current document and written to another file, which will later be sent to a
printer.

Properties
PS to EPS


ΓòÉΓòÉΓòÉ 8.1. Properties ΓòÉΓòÉΓòÉ

Some printer drivers allow extra properties to be specified. If two sections
are added to the gvpm.ini file for these printer drivers, GSview will enable
the Properties button which will display the Edit Properties dialog box. The
following example shows how to add property information for the cdjcolor
driver. First add a section which gives the current values. This section, after
the first character is removed, gives the options that will appear in the
Property list box. The first character is s for string or d for number.

 [cdjcolor]
 dBitsPerPixel=24
 dDepletion=1
 dShingling=2
 dBlackCorrect=4

Next add a section which gives the values to display in the Value list box.

 [cdjcolor values]
 dBitsPerPixel=1,3,8,16,24
 dDepletion=1,2,3
 dShingling=0,1,2
 dBlackCorrect=0,1,2,3,4,5,6,7,8,9

GSview will also add the value [Not defined] to the listbox.

When you press the OK button in the Edit Properties dialog box, the current
settings are written to the gvpm.ini file.

When GSview prints a file, it will give Ghostscript the contents of the
[cdjcolor] section of gvpm.ini as follows:

 -dBitsPerPixel=24 -dDepletion=1 -dShingling=2 -dBlackCorrect=3

If the value of a property is [Not defined], that property will not be sent to
Ghostscript.

Some entries for the cdj family of drivers are supplied in the property.ini
file that comes with GSview.


ΓòÉΓòÉΓòÉ 8.2. PS to EPS ΓòÉΓòÉΓòÉ

In general, it is not possible to convert a PostScript file to EPS. However,
many single page PostScript files can be converted to EPS by changing the first
line of the file to

 %!PS-Adobe-3.0 EPSF-3.0

and then adding or fixing up the %%BoundingBox comment.

When used incorrectly, the PS to EPS command can produce PostScript files with
incorrect DSC comments.  Such a document will cause problems when you try to
include it inside another document.

To convert a PostScript file to EPS, the original file must be a single page
document.  If the document contains DSC comments and is multi page, extract the
desired page with File | Extract. If the document does not contain DSC
comments, you will need to edit the file by hand to extract the desired page.

EPS documents must not use any of the following operators:

 banddevice   clear         cleardictstack  copypage
 erasepage    exitserver    framedevice     grestoreall
 initclip     initgraphics  initmatrix      quit
 renderbands  setglobal     setpagedevice   setpageparams
 setshared    startjob      letter          note
 legal        a3            a4              a5

The following operators should be used with care:

 nulldevice   setgstate     sethalftone    setmatrix
 setscreen    settransfer   setcolortransfer

It is your responsibility to make sure that the above requirements are met.

To test if a document contains any of the above operators, select Options | EPS
Warn and then Open the desired document. After the page has been displayed,
look in the Ghostscript text window. If any of the above operators have been
used you should see lines like:

 Warning: EPS files must not use ...

If you find these warnings then do not use PS to EPS. Remember to turn off EPS
Warn afterwards.

A document must be displayed before PS to EPS is used. The document must
contain a showpage. This is required so that the bounding box can be measured.

For documents without DSC comments, PS to EPS allows a bounding box to be
specified, then writes out an EPS file consisting of an EPS wrapper around the
original document.

For documents with DSC comments, PS to EPS will change the first line of the
file to

 %!PS-Adobe-3.0 EPSF-3.0

then allows the %%BoundingBox comment to be changed or added.

For EPS documents, PS to EPS allows the %%BoundingBox comment to be changed.

PS to EPS does not clip the document to the %%BoundingBox. To do so would
require changing the PostScript code itself. PS to EPS only changes the DSC
comments.

PS to EPS does not add a preview to a document. If you want a preview you add
it with Edit | Add EPS Preview after first creating an EPS file with a correct
%%BoundingBox.

See also Add EPS Preview, Extract, EPS Warn.


ΓòÉΓòÉΓòÉ 9. Text Extract and Find ΓòÉΓòÉΓòÉ

   In general, extracting text from a PostScript document is not a trivial
operation.  Words may be broken.  Text may be encoded. Ligatures may be used
(e.g replacing 'fi' with a single character). There may be no relationship
between the location of a word in the PostScript file and its location on the
page.

However, it is common for PostScript documents to contain text in the same
order as it appears on the page, and for it to be given in PostScript strings,
surrounded by parentheses.  Complete lines may be given in one string, or one
word per string.  For this sort of document, extracting text can be done with
reasonable success.

Edit | Text Extract will extract text contained in strings from specified pages
and write it to a text file. Line breaks in this text file correspond to lines
in the document. Spaces in the text file correspond to spaces within strings,
or to separate strings.  A more effective method of extracting text is to use
ps2ascii.ps supplied with Ghostscript.

Edit | Find will search for text and display the first page that contains the
text.  Find asks for a search text and a range of pages in which to search. The
preceeding comments about extracting text from a PostScript document should be
noted.  Find first extracts text from the document, then searches it ignoring
all spaces in both the document and the search text.  Case is ignored when
searching. Consequently the search text these would match both These and The
serial.  No information is given about where the word is located on a given
page because this information is not available without a complete PostScript
interpreter.

Edit | Find Next will continue the search from the next page.


ΓòÉΓòÉΓòÉ 10. Clipboard ΓòÉΓòÉΓòÉ

    The GSview window can be copied to the Clipboard as a bitmap by selecting
Copy from the Edit menu.

An alternative way to get a bitmap output from Ghostscript is to use one of the
BMP drivers.  See Print.

Paste To copies the currently displayed image (if available) to a BMP file.

Add EPS Preview takes a bitmap from the display and uses it to add a preview to
an EPS file. Add EPS Preview can create a DOS EPS file with a TIFF preview, or
an EPSI file with an Interchange preview. To use the Add EPS Preview command
the following steps must be followed.

1. Make sure the document has a correct bounding box. A bounding box can be
added or changed using File | PS to EPS.

2. Select Orientation | Portrait.

3. Select Options | EPS Clip. This will cause Ghostscript to use a display
window the size of the bounding box instead of the page size.

4. Select Media | Resolution and set a suitable resolution for the preview.  If
the resolution is too high it make the EPS file excessively large.

5. Open an EPS file that does not contain a preview.

6. Select Edit | Add EPS Preview, then the preview format, then the new EPS
filename.  GSview will write a new file containing the original PostScript EPS
file and a preview created from the display bitmap. The available preview
formats are Interchange, TIFF 4 and TIFF 5. If adding an Interchange preview,
the document must have an %%EndComments line, otherwise GSview may put the
preview in the wrong place. A TIFF 5 preview is a Class B image with no
compression as described in Appendix G of the TIFF 5.0 memorandum.  A TIFF 4
preview is almost identical to the TIFF 5 preview, but avoids using tags which
are not described in the TIFF 4 specifiation. WordPerfect 5.1 requires a TIFF 4
preview.

7. Reset Orientation | Portrait, Options | EPS Clip and Media | Resolution to
their previous values.

To extract the PostScript or Preview section from a DOS EPS file, use File |
Select File followed by Edit | Extract EPS then PostScript or Preview.

See also PS to EPS.


ΓòÉΓòÉΓòÉ 11. Options ΓòÉΓòÉΓòÉ

The Options menu has the following selections:

Ghostscript Command
Sounds
Units
Save Settings
Safer
Save Last Directory
Button Bar
Fit Window To Page
Quick Open
Auto Redisplay
EPS Clip
EPS Warn
Ignore DSC


ΓòÉΓòÉΓòÉ 11.1. Ghostscript Command ΓòÉΓòÉΓòÉ

The Ghostscript Command option allows selection of the command to use when
executing Ghostscript. A default will be constructed using the GSview path and
will look like:

 gsos2.exe -Ic:\gs;c:\gs\fonts;c:\psfonts

GSview will first attempt to find Ghostscript in the GSview directory and then
will try the PATH. If GSview still cannot find Ghostscript, use this option to
set the full pathname to Ghostscript. If you wish to specify that Ghostscript
should look for its initialisation files in a different place, modify the -I
option. Only the Ghostscript EXE and include path may be specified - other
items will confuse GSview.


ΓòÉΓòÉΓòÉ 11.2. Sounds ΓòÉΓòÉΓòÉ

The Sounds option assigns sounds to various events. For each event the sound
can be set to None, a Speaker Beep or a Wave file.

You must have a sound driver loaded before using Wave files. Wave file sounds
are not available under MS-Windows 3.0.

The events are:

Output Page: the PostScript showpage operator was executed.

No Page: an invalid page was selected. For example, pressing Prev while on the
first page of a document with DSC comments.

No Number: a command required page numbering and the document did not have page
numbering. For example, pressing Goto Page when viewing a document without DSC
comments.

Not Open:  a command required a document to be open and this was not the case.
For example, pressing Goto Page when no document is open.

Error: many types of errors.

Timeout: no response from Ghostscript within a timeout period. For example,
display snowflak.ps on a PC with a 286-12 CPU.

Start: GSview opened.

Exit: GSview closed.

The defaults are for No Page and Error to be a Speaker Beep and all other
events to be None.


ΓòÉΓòÉΓòÉ 11.3. Units ΓòÉΓòÉΓòÉ

The Units option sets the units used to display the cursor location on the
status bar.  Available units are PostScript points (pt = 1/72"), millimetres
(mm) and inches (in). The default is pt.


ΓòÉΓòÉΓòÉ 11.4. Save Settings ΓòÉΓòÉΓòÉ

  The Save Settings option saves the GSview window position, window size, last
used printer, last directory, Sounds, Units, Save Last Directory, User Defined,
Ghostscript Command, Button Bar, Fit Window To Page, Quick Open, Auto
Redisplay, EPS Clip, EPS Warn, Ignore DSC, Depth, Orientation, Media,
Resolution and Zoom Resolution options to the initialisation file gvpm.ini in
the OS/2 system directory. GSview reads this file during startup.

When the Save Settings on Exit option is checked, GSview will automatically
save the above settings when you quit GSview.


ΓòÉΓòÉΓòÉ 11.5. Safer ΓòÉΓòÉΓòÉ

When the Safer option is checked, GSview will give Ghostscript the -dSAFER
flag, which disables the deletefile and renamefile operators, and the ability
to open files in any mode other than read-only. This is the default.

When the Safer option is unchecked Ghostscript can change files.


ΓòÉΓòÉΓòÉ 11.6. Save Last Directory ΓòÉΓòÉΓòÉ

When the Save Last Directory option is checked, GSview will save the current
directory when you quit GSview.  When GSview is started next, this will be made
the current directory. This is the default.

When Save Last Directory option is unchecked, the current directory when GSview
is started will be the directory where GSview is located, or the working
directory specified by the Program Manager.


ΓòÉΓòÉΓòÉ 11.7. Button Bar ΓòÉΓòÉΓòÉ

 When the Button Bar option is checked, GSview will display a Button Bar down
the left side of the window.  This is the default. The Button Bar contains the
following items in order from top to bottom:

File | Open

File | Print

File | Info

Help | Contents

File | Goto Page

File | Next Page

File | Previous Page

Go forward 5 pages

Go back 5 pages

Increase resolution by 1.2

Decrease resolution by 1/1.2

Edit | Find

Edit | Find Next

If using the increase/decrease resolution buttons, Auto Redisplay should be
set.  Instead of using these buttons, it is also possible to use the Media |
Resolution command. When the Button Bar option is unchecked, GSview will not
display the Button Bar.


ΓòÉΓòÉΓòÉ 11.8. Fit Window To Page ΓòÉΓòÉΓòÉ

When the Fit Window To Page option is checked, GSview will shrink the window
size so that it is no larger than the page being displayed.  This is the
default.

If Fit Window To Page is unchecked, GSview will not resize the window and areas
outside the page will be drawn in light grey. This is useful if you do not wish
the window to shrink when looking at pages at low resolution.


ΓòÉΓòÉΓòÉ 11.9. Quick Open ΓòÉΓòÉΓòÉ

When the Quick Open option is checked, GSview will not reload Ghostscript
before every document, making opening of documents quicker.

GSview tries to preserve the Ghostscript state between documents, but a
document may still leave the Ghostscript interpreter in an unusual state or
cause an error.  If an error occurs, Ghostscript will close. Error messages are
displayed in the Ghostscript window. Select Redisplay to reopen the document.

If Quick Open is unchecked, GSview will close Ghostscript and restart it before
each new document or whenever the page orientation, resolution or size is
changed.


ΓòÉΓòÉΓòÉ 11.10. Auto Redisplay ΓòÉΓòÉΓòÉ

When the Auto Redisplay option is checked, GSview will redisplay DSC documents
when the Orientation, Resolution, Depth or Media are changed. This is the
default.

If Auto Redisplay is unchecked, the File | Redisplay command must be used to
redisplay a document after changing the Orientation, Resolution, Depth or
Media.


ΓòÉΓòÉΓòÉ 11.11. EPS Clip ΓòÉΓòÉΓòÉ

When the EPS Clip option is checked, GSview will clip the display bitmap to the
bounding box of an EPS file instead of using the page size specified on the
Media menu.  This is useful when adding a bitmap preview to an EPS file.

If EPS Clip is unchecked, GSview will use the page size specified on the Media
menu for EPS files.  This is the default.

EPS Clip does not alter the original document, it only affects how much of the
document is displayed by GSview.

See also Clipboard | Add EPS Preview


ΓòÉΓòÉΓòÉ 11.12. EPS Warn ΓòÉΓòÉΓòÉ

When the EPS Warn option is checked, GSview will write a prolog to Ghostscript
when each file is opened.  This prolog will produce warning messages in the
Ghostscript text window if any PostScript operators that should not be used in
EPS files are used.  An example warning message is:

 Warning: EPS files must not use /initgraphics

EPS Warn is not infallible.  It is possible to access restricted operators
without EPS Warn producing a warning.

The default for EPS Warn is unchecked.

See also PS to EPS.


ΓòÉΓòÉΓòÉ 11.13. Ignore DSC ΓòÉΓòÉΓòÉ

Some documents incorrectly claim to conform to the Adobe Document Structuring
Conventions.  Attempting to display one of these bogus documents will probably
leave GSview horribly confused and unable to display the document.  If Ignore
DSC is checked, GSview will treat the document as if it does not contain DSC
comments and will only display the pages in the original order.

The default for Ignore DSC is unchecked.


ΓòÉΓòÉΓòÉ 12. Page Orientation ΓòÉΓòÉΓòÉ

   The Portrait, Landscape, Upside-down and Seascape (reverse Landscape)
commands on the Orientation Menu select the page orientation used by the
display. Landscape implies a clockwise rotation of the paper by 90 degrees.
Seascape implies an anti-clockwise rotation of the paper by 90 degrees. These
orientation options only affect the display and do not affect the print
commands. If a DSC page orientation comment is found, the orientation will be
selected automatically.

When the Swap Landscape option is checked, GSview swaps the meaning of
Landscape and Seascape. Most of the Landscape documents that I have encountered
require a 90 clockwise rotation of the paper to view. However, there is no
standard and some documents need to be rotated the other way. The Swap
Landscape button allows GSview to automatically rotate the document the right
way in response to the %%Orientation comment in the PostScript file.

See also Page Size and Display Resolution.


ΓòÉΓòÉΓòÉ 13. Page Size and Display Resolution ΓòÉΓòÉΓòÉ

   The Resolution command on the Media menu selects the display resolution in
dots per inch. The default for a VGA display is 96 dots per inch.

For DSC conforming files, pressing the right mouse button will zoom into the
page at what is usually printer resolution. Pressing the right mouse button a
second time will zoom back out to normal display resolution. The Zoom
Resolution command on the Media menu sets the zoom resolution in dots per inch.

The Depth sub menu on the Media menu selects the display depth in bits per
pixels.

The Media menu also allows selection of page size. Available page sizes are:

 Letter          8.5 x 11   inch
 Tabloid        11   x 17   inch
 Ledger         17   x 11   inch
 Legal           8.5 x 14   inch
 Statement       5.5 x  8.5 inch
 Executive       7.5 x 10   inch
 A3              297 x 420  mm
 A4              210 x 297  mm
 A5              148 x 210  mm
 B4              257 x 364  mm
 B5              182 x 257  mm
 Folio           8.5 x 13   inch
 Quarto          8.5 x 10.8 inch
 10x14          10   x 14   inch

A user defined size can be specified in PostScript points (1/72 inch) with the
User Defined command.  A size of 480x360 points at 96 dpi will give an image
size of 640x480 pixels.

If a DSC media comment is found, the page type will be selected automatically.
If the media specification is not one of the above page types, the User Defined
size will be set.


ΓòÉΓòÉΓòÉ 14. Keys ΓòÉΓòÉΓòÉ

Following are the key assignments for GSview.

O, o  Open and display a file.  (File | Open)

C, c  Close file.  (File | Close)

N, n, +  Next Page.  (File | Next Page)

V, v, -  Previous Page.  (File | Previous Page)

G, g  Goto Page.  (File | Goto Page)

I, i  File information.  (File | Info)

R, r  Redisplay page.  (File | Redisplay)

S, s  Select file: open but don't display.  (File | Select File)

P, p  Print all or some pages to a printer.  (File | Print)

F, f  Print all or some pages to a File.  (File | Print To File)

E, e  Extract some pages to another File.  (File | Extract)

F1  Help.  (Help | Contents)

Ctrl+C, Insert  Copy displayed bitmap to clipboard.  (Edit | Copy)

Arrow Keys  Scroll by 16 pixels.

Ctrl+Left  Scroll left one screen.

Ctrl+Right  Scroll right one screen.

Page Up  Scroll up one screen (window height).

Page Down  Scroll down one screen.

Home  Scroll to top of page.

End  Scroll to bottom of page.


ΓòÉΓòÉΓòÉ 15. Command line options ΓòÉΓòÉΓòÉ

Usage:

 gvpm [/D] filename
 gvpm [/D] /F filename
 gvpm [/D] /P filename

To start GSview and display filename.ps use:

 gvpm filename.ps

To start GSview and print filename.ps using Ghostscript (File | Print) use:

 gvpm /P filename.ps

To start GSview and print filename.ps to a file using Ghostscript (File | Print
To File) use:

 gvpm /F filename.ps

To start GSview in debug mode use:

 gvpm /D

In debug mode GSview will not remove its temporary files. This is to allow
inspection of these files after GSview has finished.

GSview ignores the case of option: /p is the same as /P.


ΓòÉΓòÉΓòÉ 16. Copyright ΓòÉΓòÉΓòÉ

The About menu item shows the GSview copyright message and GSview version
number.

 GVPM.EXE - A Ghostscript graphical interface
 Copyright (C) 1993, 1994, Russell Lang.  All rights reserved.

This file is part of GSview.

This program is distributed with NO WARRANTY OF ANY KIND.  No author or
distributor accepts any responsibility for the consequences of using it, or for
whether it serves any particular purpose or works at all, unless he or she says
so in writing.  Refer to the GSview Free Public Licence (the "Licence") for
full details.

Every copy of GSview must include a copy of the Licence, normally in a plain
ASCII text file named LICENCE.  The Licence grants you the right to copy,
modify and redistribute GSview, but only under certain conditions described in
the Licence.  Among other things, the Licence requires that the copyright
notice and this notice be preserved on all copies.

    Author: Russell Lang
  Internet: [e-mail]


ΓòÉΓòÉΓòÉ 17. Common Problems ΓòÉΓòÉΓòÉ

 Problem: Can't run gsos2...

GSview requires OS/2 Ghostscript (gsos2.exe). This error message occurs if you
don't have OS/2 Ghostscript, or if GSview can't find OS/2 Ghostscript.

From the GSview menu select Options | Ghostscript Command and enter the correct
executable path and include path for Ghostscript. For example:

 c:\gs\gsos2.exe -Ic:\gs;c:\gs\fonts;c:\psfonts

You must set the include path for Ghostscript using either the -I command or
the GS_LIB environment variable.

Problem: Ghostscript starts and then immediately exits with error code 1.

Ghostscript probably couldn't find its initialisation files. Set the
Ghostscript include path by adding -Idirectory to the command in Options |
Ghostscript Command, where directory includes the name of the directory that
contains the Ghostscript initialisation files, Alternatively, set the
environment variable GS_LIB.

Read the file use.doc that comes with Ghostscript.

Problem: GSview says that a multipage PostScript file produced by MS-Windows
contains 0 pages and will only show the first page.

This is because the document does not have correct DSC comments. From the
Control Panel, select Printers, Options..., then in the Print to group box
click on the Printer radio button.  You cannot use the Print To Encapsulated
PostScript File for printing multipage files.  The correct method is to connect
the printer to FILE:. In addition, from the Control Panel select Printers,
Options..., Advanced and then check Conform to Adobe Document Structuring
Convention.

The DSC comment %%Pages: 0 means that the document does not produce any pages.
That is, the PostScript showpage operator is not used. If you find a PostScript
document that has multiple pages and contains the %%Pages: 0 comment, change
the first line from %!PS-Adobe- to %!. GSview will then ignore the DSC comments
and allow you to view all pages, but only in the original order.  Complain to
the author of the program that produced that PostScript file.

Problem: PostScript files produced by MS-Windows start with a Control-D.

Since this occurs even when the PostScript printer Conform to Document
Structuring Convention checkbox is checked, this must be considered a bug in
the MS-Windows PostScript printer driver. The bug fix is documented in the
MS-Windows PRINTERS.WRI file. Edit the win.ini file and search for the
PostScript printer section. There may be more than one.  In each of these
sections add CTRLD=0 as shown below.

 [Apple LaserWriter II NT,FILE]
 CTRLD=0

Problem: PostScript files produced by Word for Windows 6.0 cause a "Missing
%%Pages comment" message box.

Congratulations.  You have just found a mistake in the DSC comments when Word
included an EPS file.  Word should have surrounded the included EPS file with
the lines

 %%BeginDocument: filename.eps
 %%EndDocument

Because Word didn't do this, GSview can't tell how many pages are in the
document and where they are located.

Please complain to Microsoft.  There is a problem in the EPSIMP.FLT filter
version 2.01 which Microsoft needs to fix.

In the interim, you have two solutions:

1. Select Options | Ignore DSC

2. Edit the PostScript file to correct the DSC comments. Search the PostScript
file for all lines containing

  %MSEPS Preamble

From each of these lines, search forward for the start of the included EPS file
which should start with a line like

 %%PS-Adobe-3.0 EPSF-3.0

Above these lines add the line

 %%BeginDocument: AddedByHand

Then search for all lines containing

 %MSEPS Trailer

Above these lines add the line

 %%EndDocument

GSview should then be able to display the file correctly.

Problem: Ghostscript always outputs to a printer instead of the GSview window.

You must not use the GS_DEVICE environment variable.


ΓòÉΓòÉΓòÉ 18. Internals ΓòÉΓòÉΓòÉ

GSview starts Ghostscript for displaying using

 gsos2 -dBitsPerPixel=x -dSAFER -rXDPIxYDPI -gWIDTHxHEIGHT -sGSVIEW=xxxx -

where xxxx is a string used to access a named shareable memory block, two
semaphores and a queue.  These are listed in gdevpm.h. The shareable memory
block contains a bitmap in BMP format. The SYNC semaphore is not used (it is
used by gspmdrv.exe instead). The NEXT semaphore is used when waiting at each
showpage. The MUTEX is used to sychronise access to the bitmap. The QUEUE is
used by Ghostscript to notify GSview about the following significant events:
1. Starting to draw into bitmap, 2. Synchronise (redraw) page, 3. showpage
(redraw page), 4. Ghostscript is closing, 5. Ghostscript fatal error, 6.
Palette in bitmap has changed, 7. "-1 false .outputpage" is executed, 8. "-2
false .outputpage" is executed. PostScript code is piped to the Ghostscript
stdin. Ghostscript stdout goes to a window.

GSview uses temporary files of the name gvXXXXXX in the directory given by the
TEMP environment variable.

GSview starts Ghostscript for printing using

 gsos2 @optfile

optfile contains

 -dNOPAUSE
 -dSAFER
 -sDEVICE=devname
 -rXDPIxYDPI
 -gWIDTHxHEIGHT
 -sOutputFile=outfilename
 filename.ps
 quit.ps