I belive I now have a MVP

.idea/dictionaries/mburket.xml

 <component name="ProjectDictionaryState">
   <dictionary name="mburket">
     <words>
+      <w>calcuates</w>
       <w>connetion</w>
       <w>descired</w>
       <w>initalize</w>

connect.c

@@ -4,6 +4,9 @@
 
 #include "connect.h"
 #include "buffer.h"
+#include <time.h>
+
+int calc_date(char *deltaString, char *returnTime);
 
 /// Initalize the connection
 ///
@@ -65,7 +68,7 @@ int establish_connect(struct addrinfo *info) {
 /// \param path path to request
 /// \param head if true use the head method on the url
 /// \return number of bytes sent to the server
-int execate_request(int socketfd, char *hostname, char *path, int head) {
+int execate_request(int socketfd, char *hostname, char *path, int head, int date, char *date_string) {
     // Reqeust is a buffer
     GrowthBuffer request;
     // Init the buffer
@@ -87,6 +90,15 @@ int execate_request(int socketfd, char *hostname, char *path, int head) {
     appendBuffer(&request, hostLine, strlen(hostLine));
     appendBuffer(&request, hostname, strlen(hostname));
     appendBuffer(&request, "\r\n", 2);
+    // Build If-Modified-Since Header
+    if (date) {
+        char *ModLine = "If-Modified-Since: ";
+        appendBuffer(&request, ModLine, strlen(ModLine));
+        char *timeStamp = malloc(sizeof(char) * 256);
+        calc_date(date_string, timeStamp);
+        appendBuffer(&request, timeStamp, strlen(timeStamp));
+        appendBuffer(&request, "\r\n", 2);
+    }
     // Close off the request
     appendBuffer(&request, "\r\n", 2);
     appendBuffer(&request, "\r\n", 2);
@@ -117,4 +129,20 @@ int get_result(int socketfd, GrowthBuffer *recvBuff, int recvBuffSize) {
            return 0;
         }
     }
+}
+
+/// Calculates the time stamp based on the time delta string
+///
+/// \param deltaString
+/// \param returnTime
+/// \return
+int calc_date(char *deltaString, char *returnTime) {
+    int day = 0;
+    int hour = 0;
+    int min = 0;
+    sscanf(deltaString, "%d:%d:%d", &day, &hour, &min);
+    time_t n_time;
+    n_time=time(0);
+    n_time=n_time-(day*24*3600+hour*3600+min*60);
+    strcpy(returnTime, ctime(&n_time));
 }
\ No newline at end of file

connect.h

@@ -17,7 +17,7 @@
 
 void init_connection(char *hostname, int port, struct addrinfo **info);
 int establish_connect(struct addrinfo *info);
-int execate_request(int socketfd, char *hostname, char *path, int head);
+int execate_request(int socketfd, char *hostname, char *path, int head, int date, char *date_string);
 int get_result(int socketfd, GrowthBuffer *recvBuff, int recvBuffSize);
 
 #endif //COMS352_PROJECT2_PART1_CONNECT_H

main.c

@@ -30,7 +30,7 @@ int main (int argc, char **argv) {
 
     // getopts section based on
     // https://www.gnu.org/software/libc/manual/html_node/Example-of-Getopt.html#Example-of-Getopt
-    while ((c = getopt(argc, argv, "hd:")) != -1)
+    while ((c = getopt(argc, argv, "hd:")) != -1) {
         switch (c) {
             case 'h':
                 header_only = 1;
@@ -52,15 +52,12 @@ int main (int argc, char **argv) {
             default:
                 abort();
         }
+    }
 
-
-    printf("header_only = %d, timeDelta = %d, cvalue = %s\n",
-           header_only, timeDelta, cvalue);
-
-    for (index = optind; index < argc; index++)
+    for (index = optind; index < argc; index++) {
         printf("Non-option argument %s\n", argv[index]);
+    }
 
-    printf("\noptind: %s\n", (argv[optind]));
     if (argv[optind] == NULL) {
         show_help_exit(argv[0]);
     }
@@ -69,14 +66,9 @@ int main (int argc, char **argv) {
     int port = 80;
     char *page = malloc(sizeof(char) * 256);
     getUrlParts(argv[optind], &host, &port, &page);
-    printf("\nhost: %s\n", host);
     init_connection(host, 80, &addressInfo);
     int sockfd = establish_connect(addressInfo);
-    if (header_only == 1) {
-        execate_request(sockfd, host, page, 1);
-    } else {
-        execate_request(sockfd, host, page, 0);
-    }
+    execate_request(sockfd, host, page, header_only, timeDelta, cvalue);
 
     GrowthBuffer gp;
     initBuffer(&gp, 50);
@@ -87,4 +79,4 @@ int main (int argc, char **argv) {
 void show_help_exit(char *argv) {
     fprintf(stderr, "\n%s [–h] [–d <time-interval>] <URL>", argv);
     exit(EXIT_FAILURE);
-}
\ No newline at end of file
+}