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Latin1 vs UTF8

Latin1 was the early default character set for encoding documents delivered via HTTP for MIME types beginning with /text . Today, only around only 1.1% of websites on the internet use the encoding, along with some older applications. However, it is still the most popular single-byte character encoding scheme in use today. A funny thing about Latin1 encoding is that it maps every byte from 0 to 255 to a valid character. This means that literally any sequence of bytes can be interpreted as a valid string. The main drawback is that it only supports characters from Western European languages. The same is not true for UTF8. Unlike Latin1, UTF8 supports a vastly broader range of characters from different languages and scripts. But as a consequence, not every byte sequence is valid. This fact is due to UTF8's added complexity, using multi-byte sequences for characters beyond the general ASCII range. This is also why you can't just throw any sequence of bytes at it and ex...
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Processes and Call Stacks

In Windows, our process information looks something like this. On the left list here we have our process. Within it we have code sections, global variables, process heap, process resources, open files and handles, our environment block, and thread info which include our thread local storage, and stack data. And within the call stack, we have various frames which will unwind with our process, with the bottom-most function frame being the beginning of the call stack. This usually starts with a prologue involving LdrpInitializeProcess, BaseThreadInitThunk, and RtlUserThreadStart.


Inside a Process Block:
  • Code: Executable instructions
  • Global variables: Variables accessible throughout the process
  • Process heap: Dynamic memory allocation
  • Process resources: System resources assigned to the process
  • Open files and handles: Files the process has opened for reading or writing
  • Environment block
  • Threads/Thread Local Storage
  • Stack
 Inside a Call Stack:
  • Frame 0: Top-level function frame.
  • Frame 1: Calling function's frame.
  • Frame 2: Caller of Frame 1's function frame.
  • Frame 3: Caller of Frame 2's function frame.
  • Frame N: Bottom-most function frame.
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