created: 20231029134919585
creator: Octt
modified: 20231105110313014
modifier: Octt
tags: 
title: C Language

<<^wikipediaframe C_Language>>

* [[Why do many functions that return structures in C, actually return pointers to structures?|https://softwareengineering.stackexchange.com/questions/359408/why-do-many-functions-that-return-structures-in-c-actually-return-pointers-to-s]]
* [[Passing by reference in C|https://stackoverflow.com/questions/2229498/passing-by-reference-in-c]] --- "C does not support passing a variable by reference"... //Passing a pointer ''is'' passing-by-reference. This seems to be one of those facts that "savvy" C programmers pride themselves on. Like they get a kick out of it. "Oh you might THINK C has pass-by-reference but no it's actually just the value of a memory address being passed harharhar". Passing by reference literally just means passing the memory address of where a variable is stored rather than the variable's value itself [...]//
* [[Pointers in C: when to use the ampersand and the asterisk?|https://stackoverflow.com/questions/2094666/pointers-in-c-when-to-use-the-ampersand-and-the-asterisk#2094715]]
** Related: [[error: invalid type argument of ‘unary *’ (have ‘int’)|https://stackoverflow.com/questions/5455866/error-invalid-type-argument-of-unary-have-int#5455962]], this happens when using `*` against a value instead of a pointer, since you can't dereference a value from a value.

* [[strcpy vs. memcpy|https://stackoverflow.com/questions/2898364/strcpy-vs-memcpy]] --- //strcpy stops when it encounters a NUL ('\0') character, memcpy does not//, aka as the names suggest often strcpy is perfect for strings while for generic data memcpy could be needed.
* [[ISO C90 forbids mixed declarations and code in C|https://stackoverflow.com/questions/13291353/iso-c90-forbids-mixed-declarations-and-code-in-c]] --- old C standards required that new variables can be declared only before any other actual instruction in a scoped block, e.g. only at the top of a function
* [[Creating empty function macros|https://stackoverflow.com/questions/9187628/empty-function-macros]] --- only safe way is `#define SomeFunction(arg) ((void)0)`
** [[C macros, what's the meaning of ((void)0)?|https://stackoverflow.com/questions/61157541/c-macros-whats-the-meaning-of-void0]]