From b5921f2165b86a325ebc032d03c5ab91475bedd2 Mon Sep 17 00:00:00 2001
From: Ankan Poddar <friendyankan@gmail.com>
Date: Sat, 22 Dec 2018 18:02:57 +0530
Subject: [PATCH] Assignment 2

---
 half.c   | 35 +++++++++++++++++++++++++++++++++++
 square.c | 35 +++++++++++++++++++++++++++++++++++
 twice.c  | 35 +++++++++++++++++++++++++++++++++++
 3 files changed, 105 insertions(+)
 create mode 100644 half.c
 create mode 100644 square.c
 create mode 100644 twice.c

diff --git a/half.c b/half.c
new file mode 100644
index 0000000..ee1e373
--- /dev/null
+++ b/half.c
@@ -0,0 +1,35 @@
+#include <stdio.h>
+#include <unistd.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sys/ipc.h>
+
+char* itoa(int val, int base){
+    
+    static char buf[32] = {0};    
+    int i = 30;    
+    for(; val && i ; --i, val /= base)    
+        buf[i] = "0123456789abcdef"[val % base];   
+    return &buf[i+1];
+    
+}
+
+int main(int argc, char* argv[]) {
+    if (argc == 1)
+        exit(0);
+        
+    int n = atoi(argv[argc - 1]);
+    int res = n / 2;
+    printf("Halving, Current process id: %u, Current result: %d\n", getpid(), res);
+
+    char* v[argc];
+    for (int i = 1; i < (argc-1) ; i++) {
+        v[i-1] = argv[i];
+    }
+        
+    v[argc-2] = itoa(res, 10);
+    v[argc-1] = NULL;
+    
+    execvp(v[0], v);
+}
+    
diff --git a/square.c b/square.c
new file mode 100644
index 0000000..f9f7146
--- /dev/null
+++ b/square.c
@@ -0,0 +1,35 @@
+#include <stdio.h>
+#include <unistd.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sys/ipc.h>
+
+char* itoa(int val, int base){
+    
+    static char buf[32] = {0};    
+    int i = 30;    
+    for(; val && i ; --i, val /= base)    
+        buf[i] = "0123456789abcdef"[val % base];   
+    return &buf[i+1];
+    
+}
+
+int main(int argc, char* argv[]) {
+    if (argc == 1)
+        exit(0);
+        
+    int n = atoi(argv[argc - 1]);
+    int res = n * n;
+    printf("Squaring, Current process id: %u, Current result: %d\n", getpid(), res);
+
+    char* v[argc];
+    for (int i = 1; i < (argc-1) ; i++) {
+        v[i-1] = argv[i];
+    }
+        
+    v[argc-2] = itoa(res, 10);
+    v[argc-1] = NULL;
+    
+    execvp(v[0], v);
+}
+    
diff --git a/twice.c b/twice.c
new file mode 100644
index 0000000..1dca0cb
--- /dev/null
+++ b/twice.c
@@ -0,0 +1,35 @@
+#include <stdio.h>
+#include <unistd.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sys/ipc.h>
+
+char* itoa(int val, int base){
+    
+    static char buf[32] = {0};    
+    int i = 30;    
+    for(; val && i ; --i, val /= base)    
+        buf[i] = "0123456789abcdef"[val % base];   
+    return &buf[i+1];
+    
+}
+
+int main(int argc, char* argv[]) {
+    if (argc == 1)
+        exit(0);
+        
+    int n = atoi(argv[argc - 1]);
+    int res = 2 * n;
+    printf("Doubling, Current process id: %u, Current result: %d\n", getpid(), res);
+
+    char* v[argc];
+    for (int i = 1; i < (argc-1) ; i++) {
+        v[i-1] = argv[i];
+    }
+        
+    v[argc-2] = itoa(res, 10);
+    v[argc-1] = NULL;
+    
+    execvp(v[0], v);
+}
+