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POcomparing two strings in c
 

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    <p>I have a basic question on strings and char array's in C.</p> <p>below I have some basic code that compares data coming over a socket(telnet) with an existing string. This however fails. IF I compare a character in the char array it works in[1] == out[1]. Can you advise why the strings don't match and if I am missing something. Do I need to convert the char to anther type of string?</p> <p>thx Art</p> <pre><code>#include &lt;stdio.h&gt; #include &lt;unistd.h&gt; #include &lt;stdlib.h&gt; #include &lt;string.h&gt; #include &lt;sys/types.h&gt; #include &lt;sys/socket.h&gt; #include &lt;netinet/in.h&gt; void dostuff(int); /* function prototype */ void error(const char *msg) { perror(msg); exit(1); } int main(int argc, char *argv[]) { int sockfd, newsockfd, portno, pid; socklen_t clilen; struct sockaddr_in serv_addr, cli_addr; if (argc &lt; 2) { fprintf(stderr,"ERROR, no port provided\n"); exit(1); } sockfd = socket(AF_INET, SOCK_STREAM, 0); if (sockfd &lt; 0) error("ERROR opening socket"); bzero((char *) &amp;serv_addr, sizeof(serv_addr)); portno = atoi(argv[1]); serv_addr.sin_family = AF_INET; serv_addr.sin_addr.s_addr = INADDR_ANY; serv_addr.sin_port = htons(portno); if (bind(sockfd, (struct sockaddr *) &amp;serv_addr, sizeof(serv_addr)) &lt; 0) error("ERROR on binding"); listen(sockfd,5); clilen = sizeof(cli_addr); while (1) { newsockfd = accept(sockfd, (struct sockaddr *) &amp;cli_addr, &amp;clilen); if (newsockfd &lt; 0) error("ERROR on accept"); pid = fork(); if (pid &lt; 0) error("ERROR on fork"); if (pid == 0) { close(sockfd); dostuff(newsockfd); exit(0); } else close(newsockfd); } /* end of while */ close(sockfd); return 0; /* we never get here */ } /******** DOSTUFF() ********************* There is a separate instance of this function for each connection. It handles all communication once a connnection has been established. *****************************************/ void dostuff (int sock) { int n; char buffer[2]; char kjh[] = "aaa"; bzero(buffer,256); n = read(sock,buffer,255); if (n &lt; 0) error("ERROR reading from socket"); if (strcmp(ptr,kjh) == 0) { printf("they are the same: %s.\n",buffer); do_other_stuff(); } printf("Here is the message!: %s\n",buffer); n = write(sock,"I got your message",19); if (n &lt; 0) error("ERROR writing to socket"); } void do_other_stuff() { printf("function works:"); } </code></pre>
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