Using Pthread library

Author: dalmia

4-Multithreaded programming/pthreads/a.out

@@ -0,0 +1,39 @@
+#include <pthread.h>
+#include <stdio.h>
+
+int sum; /* this data is shared by the threads */
+void *runner(void *param); /* threads call this function */
+
+int main(int argc, char *argv[])
+{
+ pthread_t tid; /* the thread identifier */
+ pthread_attr_t attr; /* set of thread attributes */
+
+ if(argc != 2){
+ fprintf(stderr, "usage: a.out <integer value>\n");
+ return -1;
+ }
+ if(atoi(argv[1]) < 0){
+ fprintf(stderr, "%d must be >=0\n", atoi(argv[1]));
+ return -1;
+ }
+
+ /* get the default attributes */
+ pthread_attr_init(&attr);
+ /* create the thread */
+ pthread_create(&tid,&attr,runner,argv[1]);
+ /* wait for the thread to exit */
+ pthread_join(tid, NULL);
+
+ printf("sum = %d\n", sum);
+}
+
+/* The thread will begin control in this function */
+void *runner(void *param){
+ int i, upper = atoi(param);
+ sum = 0;
+ for(i = 1; i <= upper; i++)
+ sum += i;
+
+ pthread_exit(0);
+}