Structure Packing in C

C Programming: Structure Packing in C Programming.
Topics discussed:
1) Structure Packing.
2) The need for Structure Packing.
C Programming Lectures: goo.gl/7Eh2SS
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Axol x Alex Skrindo - You [NCS Release]
#CProgrammingByNeso #CProgramming #StructuresInC #StructurePacking #Structure&Union

[@hemasundarkasturi5439]

thank you a lot for sharing the knowledge 😊😊

[@shashankgaur18]

First view... I was totally unaware of this concept so thank you neso academy

[@joel_b9216]

Great video as always! Your videos save me so much time. Thanks a lot.

[@AbhishekSingh-cu1fe]

Thank you sir

[@embedded3696]

ultimate video, easy understanding

[@shreyasingh222]

Outstanding....

[@Cat_Sterling]

Thank you so much, had no idea that it could be done!

[@sazadahemad2799]

learnt a new thing.... thanx neso

[@oksowhat]

sir as in previous example where 12bytes were used and 3cpu cycles then still if we did't used padding then the fisrt char will use 1 byte 2nd int will use next 3 bytes of first word and 1 byte in 2nd word and 3rd char will use 1 byte in 2nd word, total of 2 cycle being used, this is inefficient

[@ankammaraochintala2509]

Thank you sir, for your knowledge transfer

[@AamirKhan-de7hg]

#include struct abc{ double x; int y; } ; int main() { printf("%d",sizeof(struct abc)); }

[@preciouslife1212]

great video sir

[@sivaramakrishna26]

The teaching about structure in detail is excellent. Can you please explain the #pragma directive in detail

[@Mehraj_IITKGP]

This directive is a special purpose directive and is used to turn on or off some features. These types of directives are compiler-specific i.e., they vary from compiler to compiler. -- For example, #pragma warn Directive is used to hide the warning messages which are displayed during compilation, it can be used as: #pragma warn +xxx (To show the warning) #pragma warn -xxx (To hide the warning) -- #pragma GCC poison is supported by the GCC compiler and is used to remove an identifier completely from the program. It can be used as #pragma GCC poison printf to poison printf keyword. Similarly, it has many uses. The only feature I use is #paragma pack(1).

[@parishush]

Thank you

[@mgproductions396]

Great video

[@johnh1353]

You should still study your target architectures and not take all structure padding as bad ... most modern processor ISA's implement a "barrel shifter" to make fetch and put single cycle operations which based on structure types and order sometimes can't help but have some padding ... Binary packing is another technique to be studied that focuses at the byte shifting .. great for implementing protocols and working within the bounds of CPU caches

[@QuratulainAzhar]

bohat achay

[@heetbhatt4511]

is that necessary to save cpu cycle?

[@vinayakgujjar9655]

Nice one, bur was not as clear as structure padding video. Concern is how processor modulates its data accessing from 8bytes at a time to 6bytes.

[@khalilchouchene7988]

That's what am asking right now

[@jeedikantivenkat7814]

First view First like First comment❤ Enough for the day .. Sir please provide videos on data structures .

[@peasant12345]

why not put low byte data types in front of high byte ones when you construct struct

[@veeraloganathanvvs5495]

If I need both and optimise code means! What we have to do. ? Structure should be properly ordering?

[@VishalMishra-jx8gs]

sir please make video for all the subject

[@AamirKhan-de7hg]

What will be the output of this program ??

[@varunsaigs9815]

Then what is the size of that var in 62 bites architecture??

[@deviganeshan838]

Sir... Pls update videos in operating system

[@gsravan7058]

But how pragma will work internally?? I want to know about internal process of pragma

[@mcbotface]

Thank you once again sir Please add more video lectures in Discrete Mathematics playlist on topics like Relations, Functions, Graph Theory, Trees, Prefix Codes, Huffman coding, etc.

[@FitTechCricketer]

sir,but In 64 bit architecture 1 word =8 byte so without pragma pack it should be 8 na for char,int,char

[@pradhanan9413]

Ya

[@pradhanan9413]

But it's showing me 12 as output....please explain

[@suhanibohra623]

is it always recommended to pack structures?

[@RamKumar-fs9sd]

but which is more important for industry concepts?

[@harshgupta4326]

sir is padding faster than packing

[@taranjeetsingh6869]

What would be loss if cpu cycle is increased?

[@xrafter]

More cpu cycle mean more time

[@nishantraj9762]

Why (char*) ? Why not (char)

[@yogeshmhanta2902]

How many wastage of cpu cycles in a above program.

[@worldproducer567]

2 cycles Assuming Char takes 1 byte Int takes 4 byte because char a covers one word, int b covers 2 bytes of first word and 2 bytes of the next adjacent word, and char c covers one byte in the same word . Therefore two words are used and thus 2 CPU cycles are wasted

[@arvindersingh9863]

--attribute--((packed)); do same?

[@venusdille8179]

Tttoooppp

[@mazharkhaliq1971]

Thank you for the knowledge 😊

[@ElifArslan-l9g]

thank you