Use dar to backup large directories to multiple DVDs.

I have a large directory of research data. Cannot use tar to do the work because the file size limit of tar is 4G. Finally get dar, which works very well. Use the following to backup


>> sudo dar -s 10M -c test -R / -g /Volumes/DATABACKUP/Research/ -v


The above means: backup all the stuffs in directory /Volumes/DATABACKUP/Research/. Since there are so many files in this directory, dar will make sure that the files it generate is small enough for later use. Here with -s 10M, dar generates files of 10 M.  -v is used to display message. -R is used to set the ROOT directory, which is / here. -g restricts the directory to /Volumes/DATABACKUP/Research/.

Doxygen graph interpretation.

call graph: 

A ------> B: A is called by B. 

Classes: 

A ----> B: Actually B is the parent class! One way to understand/remember this that A is called as B (for example: A is a dog class; B is an animal class. Dog is called as animal. 

Qt and gsl library problem.

ld: warning: in /usr/local/lib/libgsl.dylib, file is not of required architecture

Solution: 

open the Makefile and: 

1. CFLAGS: get rid of "arch i386'. 

2. CXXFLAGS: get rid of "arch i386"

3. comment LFLAGS. 

4. QMAKE_COMP_QMAKE_OBJECTIVE_CFLAGS: get rid of "arch i386". 

then save the Makefile and do: 

> make clean

> make

you will get warning but it should pass!

dyld: Library not loaded

After I installed qwt, everything seems to work. However, whenever I execute the program (examples), I got into trouble. When I used Qt creator to open one particular example and build it, I encountered the following error: 
dyld: Library not loaded: libqwt.5.dylib
I searched the internet and did not find any easy solution. Proudly I used the following command to fix the problem. It may not be elegant but it works for me.


sudo ln -s /usr/local/qwt-5.2.0/lib/libqwt.5.dylib /usr/lib/libqwt.5.dylib