Technical Questions and Answers

uDraw(Graph):

1. Error after upgrade: "Default language file differs..."
   
2. Using '\' in Filenames (Windows^®)
   
3. .udg file not modified after saving
   
4. Hibernation not possible (Windows^®)
   
5. Testing API commands with option -pipe (Windows^®)
   
6. Export graph without display
   
7. How to print a graph larger than a single page?
   

uDraw(Graph):

1. Question: After an upgrade, why does uDraw(Graph) start with an error message "Default language file version differs from uDraw(Graph) version"?
   Answer: The environment variable UDG_HOME still points to the directory with the old installation. Under Windows^® just delete the environment variable. It is not required any more by recent versions of uDraw(Graph).
   

---

2. Question: I am using the backslash path delimeter ('\') under Windows^®. Why are my API calls with file name parameter not accepted?
   Answer: The API expects the file name as a string in C-notation, where the backslash has special meaning. You have to use a slash ('/') instead of backslash ('\') and everything works fine.
   

---

3. Question: I have loaded a *.udg file, modified it with the grapheditor and saved it with the "Save" option in the "File" menu. The *.udg file does not change.
   Answer: The "Save" option will always save the graph into a *.status file and therefore leaves the *.udg file untouched. Use the "Save As..." option in the "File" menu to overwrite the *.udg file.
   

---

4. Question: uDraw(Graph) does not allow me to suspend Windows^® (enter hibernation), when an application is connected. Why?
   Answer: uDraw(Graph) does not support suspension with an application connected yet. Either uDraw(Graph) or even the complete operating system would not resume without errors.
   

---

5. Question: I tried the -pipe command line option under Windows^® and wanted to type some API commands manually.
   Answer: For Windows^® there are two almost identical versions of uDraw(Graph). The one you get with the distribution is compiled as a Windows^® application and does not offer the possibility to type API commands on a console. The other version can be downloaded by need. It is compiled as a console application and opens a console where you can enter your commands.
   

---

6. Question: How to export a graph without a display?
   Answer: To be able to export files uDraw(Graph) needs a display and must not been started with the -server option. If a real display is not available or the windows of uDraw(Graph) shall not appear on that display, you can use Xvfb on many platforms. Xvfb is a X11-Server from The XFree86^TM Project, Inc., which uses virtual framebuffers for display.
   

---

7. Question: How to print a graph larger than a single page?
   Answer: You'll want to tile the graph on several pages and stick them together. In the uDraw(Graph) print dialog, you can select "print to file" in order to get a PostScript^® file. Then you can use a third party tool to split this PostScript^® file to several smaller pages, for example "poster" for UNIX^® and Windows^®. It can be downloaded here: http://www.ctan.org/tex-archive/support/poster/
   

---

If your question is not answered yet, please send e-mail to uDrawGraph.at.informatik.uni-bremen.de.