Section: User Commands (1)
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sdump, sdumpopt - graphics terminal screen dump  


sdump [options] [lp-options] [file] ...

sdumpopt [options]  


Sdump takes a copy of the screen of a graphics terminal (or more typically the window from which it is run) and prints it out on a printer. Normally, screen dumps are produced in a one step process: after having made a copy of the screen's current contents, sdump automatically calls lp(1) or lpr(1) to perform the printing in the background.

Screen dumps can also be handled using a two step process. Using the -save fname option, you can get sdump to save a copy of the screen into the specified file fname, using the image file format described in gpsras(5). Later, you can invoke sdump, giving it one or more file arguments; it will print these saved screen images on one page. The file name - stands for the standard input, and may be given along with other file names. If no file names are given, the standard input is not assumed. Rather, without file name arguments, sdump will grab a screen image and print it or save it.

Sdumpopt allows you to change the default actions taken by sdump when certain options are omitted from its command line. The options you give to sdumpopt are saved in the file .sdumprc in your home directory. Sdump looks at this file to get its default options. You can view your current defaults by invoking sdumpopt with no arguments.

The options recognised by both commands are:

-res dpi
Print the image at a resolution of dpi dots/inch. Affects only the printing phase. Values allowed are device dependent. For the HP LaserJet, they are 300, 150 (the initial default), 100, and 75.
-rot deg
Rotate the image counter-clockwise by deg degrees. Affects only the printing phase. Values allowed are device dependent. For the HP LaserJet, they are 0, 90, 180, and 270 (or -90, the initial default).
Print an "inverse video" image. Dark dots on screen print as black dots, with the assumption being made that the image is drawn using dark colours on a light or white background. Historically, this was known as inverse or reverse video, because the norm used to be white on black.. This option is normally on by default. Affects only the printing phase.
Print a positive image. I.e. disable -inv option, for cases where the image on screen is white on black, and you want the white parts printed black.. Affects only the printing phase.
-lines n
Grab n raster scan lines from the screen or window. Initially, the entire screen or window is grabbed. This option historically allowed you to eliminate the bottom few lines. It is currently ignored on X Window based systems.
-save fname
Save the screen image in the named file, rather than automatically printing it. By default, the image is saved in gpsras(5) format, for later printing by the sdump command. However, you can append any of these file name suffixes to fname to get the file saved in the corresponding format: .gif, .tif (or .tiff), .jpg (or .jpeg), .ppm, .pbm, .png, .pdf, .eps (or .ps), .bmp, .xpm or .xbm. Of all of these, .png is probably the best choice to get a reasonably compact file with the least chance of losing image detail or colour. For these file formats, you will not be able to print out the saved image files directly using the sdump command, but you can easily use them to import images into other programs. You can also specify the reserved file name .psprinter, which will cause sdump to print out the screen dump to a PostScript printer. This allows printouts of color or grayscale screen dumps, rather than the default black on white printouts normally produced, but it is limited to PostScript compatible printers. (On most Linux systems and Mac OS X 10.3 and up, all supported printers are essentially PostScript compatible because the printing system emulates PostScript for non-PS printers.)
Disable the -save option, and automatically print the screen image.

Any other option arguments to sdump are passed along to lp.

If you use the -save option with sdumpopt, sdump will not write all screen images to the same file by default. Rather, it will "increment" the file name saved in .sdumprc, so that the next screen image goes to a new file.

Although sdump can be invoked directly as a UNIX command, it is often invoked automatically when a screen dump request is received by programs such as analysis, frmsel, peel, raster, and wtsum. A screen dump is requested in these programs by pressing the quit key, normally Control-B, or by selecting Plot/Video or Hardcopy/Video , when available, from the programs' menus. When invoked in this way, sdump is not given any options or file name arguments. Its options can be changed via sdumpopt.

The printing of gpsras(5) format image files is handled by the lp interface program for the default printer, or by the filter set up by selectlp(1) on lpr based systems.  


The commands below illustrate the use of the -save option:

sdumopt -save screen1 -lines 600
sdump -save dumpfile
sdump -lines 560
sdump -res 300 -rot 0 dumpfile screen*

The first command sets up .sdumprc in your home directory. The second command saves the screen image in the file screen1, and increments the file name stored in .sdumprc. The third command saves the screen image in dumpfile, and doesn't change the file name stored in .sdumprc. The fourth command saves the top 560 lines of the screen image in the file screen2. The fifth command prints the saved images at 300 DPI, in the given order, on one page in portrait orientation. The last command shows the current options, which should include "-save screen3 -lines 600."  


When the X Window version of this program is run on an X Window terminal, it will grab the image of the window selected by the WINDOWID environment variable. All the X Window versions of programs in this package set this variable when they create a window, as does the xterm program. Unlike the other X Window programs in this package, sdump will not recognise the usual X command line options, such as -display. (The environment variable for setting this option will work, however.)  


~/.sdumprc                             user defaults


gpsras(5), analysis(1), frmsel(1), peel(1), raster(1), wtsum(1)  


Sdump saves or prints only black and white images. Images from a colour display are converted to black and white by the xpr utility, which maps all light colours to white and dark colours to black. This may not be quite what you expect if some of the colours drawn on the background of your window are a bit on the light side.



This document was created by man2html, using the manual pages.
Time: 17:58:06 GMT, February 20, 2019
Copyright © G. R. Detillieux, Spinal Cord Research Centre, The University of Manitoba.