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Udf debug

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Debugging a Fluent udf using gdb

 1. build libudf using GUI
 2. open with a text editor the file libudf/src/makefile
 3. search for CFLAGS_LNAMD64 (or your appropriate platform)
 4. change the option "-O" with "-O0 -g" and save the file
 5. go to the libudf directory "cd libudf"
 6. "make clean"
 7. "make; cd ../"
 8. load the new libudf in fluent and start running the udf
 9. Identify the process id of fluent "ps -e | grep fluent.12.0.16"
10. start the debugger "gdb" in the same directory with "libudf" (should be the same as the case directory)
11. attach to the fluent process "attach 10304"; now fluent is interrupted
12. "backtrace" or "frame" to see where we are in the code
13. "break filename.c:line_nr" - put a break point in your udf source at a specified line
14. "continue" - now fluent gets alive again until it hits your breakpoint
15. once the breakpoint is hit, use "print/step/next..." to follow your code step by step
16. if the bug is found or you got bored, then is time for a detach: "detach"
17. "quit"
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