It’s the other way around. When ios::ate is set, the initial position will be the end of the file, but you are free to seek thereafter. When ios::app is set, all output operations are performed at the end of the file. Since all writes are implicitly preceded by seeks, there is no way to write elsewhere.
Most likely cause is that you’re not linking in the object created from Agent.cpp. You should check to ensure that it’s part of the project and that you’re using the correct version, compiled with this current compiler as well (since you state you haven’t touched it in a while, it may be that the objects were … Read more
static in this context means “local” (to the translation unit). There will be multiple copies of read_mess in your program, one per translation unit which is not the same thing as a header file. (In your case you can most likely approximate “translation unit” as .cpp or .c or .cc file). Probably what you meant to do was to declare an extern variable, or static class … Read more
In switch, the expression must be of “an integral type or of a class type for which there is an unambiguous conversion to integral type” (quoting VS2008 docs). A string class doesn’t have “unambiguous conversion to integral type”, like a char does. As a work-around: Create a map<string, int> and switch on the value of the map: switch(command_map[command]) ` Do a set of if/else instead of … Read more
Arrays can only be passed by reference, actually: This prevents you from doing things like: To be able to pass an arbitrary size array to foo, make it a template and capture the size of the array at compile time: You should seriously consider using std::vector, or if you have a compiler that supports c++11, std::array.
pair is name of a standard class and with the using namespace std, there is a collision. Several solutions : Rename your class to something else. Dont use the using statement
Check the PYTHONPATH and PYTHONHOME environment variables and make sure they don’t point to Python 2.x. http://bugs.python.org/issue11288
EXC_I386_GPFLT is surely referring to “General Protection fault”, which is the x86’s way to tell you that “you did something that you are not allowed to do”. It typically DOESN’T mean that you access out of memory bounds, but it could be that your code is going out of bounds and causing bad code/data to … Read more
Defining the body of the constructor INSIDE the class has the same effect of placing the function OUTSIDE the class with the “inline” keyword. In both cases it’s a hint to the compiler. An “inline” function doesn’t necessarily mean the function will be inlined. That depends on the complexity of the function and other rules.
This error means that you are trying to show an empty image. When you load the image with imshow, this is usually caused by: The path of your image is wrong (in Windows escape twice directory delimiters, e.g. imread(“C:\path\to\image.png”) should be: imread(“C:\\path\\to\\image.png”), or imread(“C:/path/to/image.png”)); The image extension is wrong. (e.g. “.jpg” is different from “.jpeg”); You don’t have the rights … Read more