Category "c"

How to delete or clear all the messages from the POSIX message queue in c?

I want to delete all the messages from the POSIX message queue. I searched on the internet but I didn't find any way to do it instead I found the way to delete

What value does the compiler assign to an uninitialised member of a const struct in C?

Say I have a struct typedef that is: typedef struct { int32_t memberOne; int32_t memberTwo; } myStruct_t; I instantiate a const of that type as follows

Why does GCC include an "empty" XOR

I have following piece of code: typedef struct { int x; int y; int z; int w; } s32x4; s32x4 f() { s32x4 v; v.x

does pthread_join affects concurrently

I want to run all threads concurrently. If I use pthread_join function does it affect running of threads concurrently? pthread_join(..)

What is the first parameter of curl_easy_escape for?

The curl_easy_escape function of curl takes a CURL* as its first parameter, as curl’s documentation indicates: char *curl_easy_escape(CURL *curl, const ch

Adding a tab in a GTK-Notebook when using Glade

I have written a C-program and am studying GTK and Glade to build a GUI and now I am stuck for at least two days: I need a notebook with one tab. In this tab i

What is the difference between these two code structure? Nested vs single line code

if (x>0 && x<6) { break; } else if(x>6) { break; } versus if (x>0) { if (x<6)

c port listener client disconnects after 1 message

I did create a program that listens on a port and prints the message out on the terminal. My problem is, that I want to connect with telnet (telnet localhost 13

Draw a GtkImage with Cairo

I tried the solutions proposed in similary notes (How to create a gtkimage from a cairo context, How do I create a gtkimage from a cairo surface) but they didn'

Program behaves different when running with Valgrind

I have a problem debugging my application with Valgrind (memcheck). It behaves differently than when I run it standalone. There is a place in the code where it

up to 20% Numerical error or Bug in ten line code block [closed]

Rewriting a single tiny block of code of an application has yielded a considerable performance improvement. The code is 100% sequential, thus

Function-like macro, 'REPORT_ERROR', defined [MISRA 2012 Directive 4.9, advisory]

I have defined the MACRO, which will call the function and pass the argument. Getting below MISRA warning for this case. Is it not allowed? How to avoid this?

PThreads is not providing a program speedup over serial code

I am creating 2 programs to test the differences in run time of serial matrix multiply vs that of parallel matrix multiply. The parallel code that I have writte

Multithreaded socket programming : sharing variable

Hi I want to implement a ring of sockets .For example IP address 127.0.0.1 listens to 127.0.0.3 and this one listens to 127.0.0.2. They are supposed to share so

Why is my if block not getting executed in my C program?

Why is the if block not executed in the code below? #include <stdio.h> #include <stdlib.h> int main() { printf("--------------------------------

What is cryptic line of code for this statement? [closed]

For example: temp->next = NULL is same as (*temp).next = NULL list->next->next = temp is same as ??

Why is if (2 < 9 < 3) true?

This was a question in my preparation exam: int val = 0; int x = 0; int y = 1; if (x < val < y) printf(" true "); else printf(" false "); Why is

What are the examples of non-ISO practices, which are not found by -pedantic?

https://gcc.gnu.org/onlinedocs/gcc/Warning-Options.html : Some users try to use -Wpedantic to check programs for strict ISO C conformance. They soon find that

Recursive Function using MPI library

I am using the recursive function to find determinant of a 5x5 matrix. Although this sounds a trivial problem and can be solved using OpenMP if the dimensions a

How kernel know which driver to be called when we are calling any socket from user-space?

I am using IWD as a wireless daemon in userspace. Driver and firmware are loaded. When the socket is called by IWD using nl80211, it passes to nl80211 and than