some problems about c++ try catch [closed]

by

Exceptions are brutal break of the normal flow of execution. The error correcting flow is to find a catch that correspond to the object thrown; this may lead to several function calls reverse traversal. This is why it needs care to use them, you have two flow of execution : the normal one, and the error one.

If the exception thrown is catched by the catch-block directly after, then you just have to set your variable to 0 in the catch-block.

It not, a good solution is RAII (as suggested in comments). RAII is a very simple idea. As you know that every object created on stack at the entry of any block is destroyed when control leave the block, the idea is to build an object that encapsulate something, so that the destructor will be called whatever happens:

class GlobalControl {
  public:
    GlobalControl() { myglob = 1; } // RAII
    ~GlobalControl() { myglob = 0; } // RRID
};

... // somewhere else
try {
  GlobalControl c; // ctor call init glob to 1
  ...
} // whatever will happens, leaving this block cause a call to dtor of c
catch (...) {
}

RAII stands for Resource Acquisition Is Initialization, here your resource acquisition is to set your global to 1, and this is made in the initialization part of the object. RAII should be called RAIIRRID, RAII + Resource Releasing Is Destruction (the resource release is to set your global to 0, and this is made in the destructor).

More Related Contents:

  1. How do I find the location of the executable in C? [duplicate]
  2. Child process receives parent’s SIGINT
  3. Spinlock versus Semaphore
  4. fork() and output
  5. How to set breakpoints on future shared libraries with a command flag
  6. /usr/lib/x86_64-linux-gnu/libstdc++.so.6: version CXXABI_1.3.8′ not found
  7. Is there an equivalent to WinAPI’s MAX_PATH under linux/unix?
  8. print call stack in C or C++
  9. C++ cross-compiler from Windows to Linux [closed]
  10. How to install the Raspberry Pi cross compiler on my Linux host machine?
  11. In C how do you redirect stdin/stdout/stderr to files when making an execvp() or similar call?
  12. Checking if a directory exists in Unix (system call)
  13. How to create a single instance application in C or C++
  14. C++ standard library and Boehm garbage collector
  15. Get the compiler options from a compiled executable?
  16. Send and Receive a file in socket programming in Linux with C/C++ (GCC/G++)
  17. Is it safe to fork from within a thread?
  18. Compilation fails with “relocation R_X86_64_32 against `.rodata.str1.8′ can not be used when making a shared object”
  19. Linking libstdc++ statically: any gotchas?
  20. How to get a list of video capture devices (web cameras) on linux ( ubuntu )? (C/C++)
  21. Why does the library linker flag sometimes have to go at the end using GCC?
  22. C++ new operator thread safety in linux and gcc 4
  23. Linking g++ 4.8 to libstdc++
  24. How to pretty-print STL containers in GDB?
  25. Is there any standard way of embedding resources into Linux executable image? [duplicate]
  26. Command working in terminal, but not via QProcess
  27. “relocation R_X86_64_32S against ” linking Error
  28. Ctrl + C interrupt event handling in Linux
  29. Large 2D array gives segmentation fault
  30. On OS X, simple C++ program gives incorrect results (which are a result of command-line options ‘c++03’ vs ‘c++11’)

Leave a Comment