Updated undefined c notes

2 files changed, 65 insertions, 1 deletions

diff --git a/md/notes/undefined_c/titles.md b/md/notes/undefined_c/titles.md
index e3e015d..11d5271 100644
--- a/md/notes/undefined_c/titles.md
+++ b/md/notes/undefined_c/titles.md
@@ -3,22 +3,82 @@ keywords:c,linux,asm
 
 # Undefined C
 
+There is possible to piece of code inside online c compiler like https://www.onlinegdb.com/online_c_compiler
+Or run locally
+
 ## Syntax
 
 ### Variables
+
+Standard list of available types
+
+#### Check type size
+
+All types have size that are declared in bytes. Some of the types are machine dependents.
+like int/long, if there is needed machine independent types then there are int32_t/uint32_t/int64_t/uint64_t
+
+Each architecture 8bit/16bit/32bit/64bit will have different size for those types
+
+Use __sizeof()__
+
+Running on x86 machine
+```c
+#include <stdint.h>
+#include <stdlib.h>
+#include <stdio.h>
+int main() {
+    printf("Sizeof int %lu\n",sizeof(int));
+    printf("Sizeof int32_t %lu\n",sizeof(int32_t));
+    printf("Sizeof int64_t %lu\n",sizeof(int64_t));
+    printf("Sizeof long %lu\n",sizeof(long));
+    printf("Sizeof long long %lu\n",sizeof(long long));
+}
+```
+
+Defined macros'es to get type max and min values are
+
+https://en.cppreference.com/w/c/types/limits
+
+```c
+#include <limits.h>
+int main() {
+    printf("INT_MIN %d\n",INT_MIN);
+    printf("INT_MAX %d\n", INT_MAX);
+    printf("LONG_MIN %ld\n",LONG_MIN);
+}
+```
+
+#### How to shoot the leg
+
+When code suppose to run on 32bit and 64bit platform the size of type may vary. n
+Need to take in account this case.
+
+
+
+
+
 ### Functions
+
+
+
 ### If statement
 ### For cycle
 ### Structure
 ### Recursion  
 ### Macro
+### Signed/Unsigned
+### Endianess 
 ### Styles
+### Compiler flags
 
 ## Base usage
 
 ### Kernel module
 ### Write plugins
 
+
+### Intermediate usage
+
 ## Linking
 ### Creating shared library
 ### Create static libraries
@@ -41,6 +101,9 @@ keywords:c,linux,asm
 ### Cross compile
 ### Different flags
 ### Check architecture
+### ARMv8
+### AVR8
+
 
 ## Graphics
 
diff --git a/md/writeup.md b/md/writeup.md
index 31f1040..041bfca 100644
--- a/md/writeup.md
+++ b/md/writeup.md
@@ -4,7 +4,8 @@ title: Writeup page
 
 ## Writeup's
 
-<!--[AM modulation](writeup/am_modulation.md)  -->
+<!--[AM modulation](writeup/am_modulation.md)-->
+
 [BladeRF quick guide](writeup/bladerf_quick_guide.md)    
 [Writing linux mount utility](writeup/writing_linux_mount_utility.md)  
 [Naive FFT implementation in C](writeup/naive_fft_implementation_in_c.md)