gcc options explained.

"It combines the most recent stable release of the GCC toolset with the free and open-source MinGW or MinGW-w64 runtime APIs to create a LIBRE alternative to Microsoft's compiler and platform SDK."

"It does have a -O3 option --which is for optimization level."

"The reason for the error and the reason why both solutions work is that a label, including a case label, can only precede a statement."

"The void pointer, or void*, is supported in ANSI C and C++ as a generic pointer type. A pointer to void can store an address to any data type, and, in C, is implicitly converted to any other pointer type on assignment, but it must be explicitly cast if dereferenced inline."

"Creating a pointer doesn't creat a space to write someting in memory, it's just a pointer with some random value."

"This means a static variable is one that is not seen outside the function in which it is declared but which remains until the program terminates. It also means that the value of the variable persists between successive calls to a function. The value of such a variable will remain and may be seen even after calls to a function."

"Forcing a flush guarantees that the prompt will be visible before blocking for input:"

printf ( "Enter some input: " );
fflush ( stdout );
fgets ( input, sizeof input, stdin );

"A tutorial for Macintosh users interested in learning to program their Macintosh using Xcode and the C programming language. It assumes no prior knowledge of programming."

Install Xcode, then open the Terminal and type: gcc customCode.c -Wall -o customOutputName

"The "right-left" rule is a completely regular rule for deciphering C
declarations. It can also be useful in creating them."

"...an inline function is a programming language construct used to tell a compiler it should perform inline expansion on a particular function. In other words, the compiler will insert the complete body of the function in every place in the code where that function is used."

"The purpose of typedef is to assign alternative names to existing types, most often those whose standard declaration is cumbersome, potentially confusing, or likely to vary from one implementation to another."

Under C convention (such as in the C standard library), types declared with typedef end with '_t' (e.g., size_t, time_t).