What Is *.O File

What is the reached end of file while parsing error, and how can I avoid this error in the future?

You could avoid this error by fixing the syntax in the code causing the parser to expect additional closing syntax indicators (like a right curly-brace). Also check the responses to the duplicate questions because they clearly explain what are generally the syntactical causes of same error.

What is the End Of File/Stream keyboard combination to use with System.in.read()

Control + D should send the EOF character as excepted , but it is an bug in Eclipse.

One of the user reported as

    In Kepler 4.3 eclipse.buildId=4.3.0.M20130911-1000 on Linux the problem 
    still exists in the Java console. I found the following workaround:

    If you leave the console to focus on another view, and then refocus on the console,
    then Ctrl-D (EOF) works as expected.

Follow here

When using Eclipse in Windows, Control + Z sends the EOF character.

What is datatype of FILE?

It is what is typically termed an opaque data type, meaning it's typically declared as a simple structure, and then internally in the OS libraries the FILE pointer is cast to the actual date-type of the data-structure that the OS will use access data from a file. A lot of these details are system-specific though, so depending on the OS, the definition may differ.

What is *.o file?

A file ending in .o is an object file. The compiler creates an object file for each source file, before linking them together, into the final executable.

What is default directory of File.Open?

From the File.Open MSDN documentation:

The path parameter is permitted to specify relative or absolute path information. Relative path information is interpreted as relative to the current working directory. To obtain the current working directory, see GetCurrentDirectory.

Why are C++ OBJ files important?

.obj files (.o files on Linux/Unix) are compiled source files, there will indeed be one for each .cpp file, or more formally "compilation unit". They are produced by the compilation phase of building a project.

These .obj files are then combined by linker either to an application, usually .exe file on Windows, or a library file, which on windows can be a .dll for dynamic library, or .lib for static library (which is basically a collection of .obj files in one packed into one file, see below). On Unix-like platform application usually has no extension, and dynamic library has .so extension, and static library has .a extension.

You do not see .obj files or static .lib files with programs, because they are not needed at runtime, they are used only by linker. When you run the linking phase of building a project, linker combines all the needed .obj files into .exe and .dll files (or equivalent), which are used at runtime.