我的 C 程序没有将它正在显示的相同数据写入文件。如何将输出到屏幕的内容保存在文件中。我正在尝试保存网页,文件名由第三个选项定义,[站点] [页面] [路径]
#include <stdio.h>
#include <sys/socket.h>
#include <arpa/inet.h>
#include <stdlib.h>
#include <netdb.h>
#include <string.h>
int create_tcp_socket();
char *get_ip(char *host);
char *build_get_query(char *host, char *page);
void usage();
#define HOST "coding.debuntu.org"
#define PAGE "/"
#define PORT 80
#define USERAGENT "HTMLGET 1.0"
#define OS "mac osx"
int main(int argc, char **argv)
{
struct sockaddr_in *remote;
int sock;
int tmpres;
char *ip;
char *get;
char buf[BUFSIZ+1];
char *host;
char *page;
char *HTMLfile;
if(argc == 1){
usage();
exit(2);
}
host = argv[1];
if(argc > 2){
page = argv[2];
}else{
page = PAGE;
}
HTMLfile = argv[3];
sock = create_tcp_socket();
ip = get_ip(host);
fprintf(stderr, "<!--\nIP is %s\n", ip);
remote = (struct sockaddr_in *)malloc(sizeof(struct sockaddr_in *));
remote->sin_family = AF_INET;
tmpres = inet_pton(AF_INET, ip, (void *)(&(remote->sin_addr.s_addr)));
if( tmpres < 0)
{
perror("Can't set remote->sin_addr.s_addr");
exit(1);
}else if(tmpres == 0)
{
fprintf(stderr, "%s is not a valid IP address\n", ip);
exit(1);
}
remote->sin_port = htons(PORT);
if(connect(sock, (struct sockaddr *)remote, sizeof(struct sockaddr)) < 0){
perror("Could not connect");
exit(1);
}
get = build_get_query(host, page);
fprintf(stderr, "nQuery is:\n<<START>>\n%s<<END>>\n-->\n", get);
//Send the query to the server
int sent = 0;
while(sent < strlen(get))
{
tmpres = send(sock, get+sent, strlen(get)-sent, 0);
if(tmpres == -1){
perror("Can't send query");
exit(1);
}
sent += tmpres;
}
//now it is time to receive the page
memset(buf, 0, sizeof(buf));
int htmlstart = 0;
char * htmlcontent;
while((tmpres = recv(sock, buf, BUFSIZ, 0)) > 0){
if(htmlstart == 0)
{
/* Under certain conditions this will not work.
* If the \r\n\r\n part is splitted into two messages
* it will fail to detect the beginning of HTML content
*/
htmlcontent = strstr(buf, "\r\n\r\n");
if(htmlcontent != NULL){
htmlstart = 1;
htmlcontent += 4;
}
}else{
htmlcontent = buf;
}
if(htmlstart){
fprintf(stdout, "%s", htmlcontent);
}
FILE *f;
f = fopen(HTMLfile, "w");
fprintf(f, "%s", htmlcontent); //stderr, "%s"
fclose(f);
memset(buf, 0, tmpres);
}
if(tmpres < 0)
{
perror("Error receiving data");
}
free(get);
free(remote);
free(ip);
close(sock);
return 0;
}
void usage()
{
fprintf(stderr, "USAGE: htmlget host [page]\n\
\thost: the website hostname. ex: coding.debuntu.org\n\
\tpage: the page to retrieve. ex: index.html, default: /\n");
}
int create_tcp_socket()
{
int sock;
if((sock = socket(AF_INET, SOCK_STREAM, IPPROTO_TCP)) < 0){
perror("Can't create TCP socket");
exit(1);
}
return sock;
}
char *get_ip(char *host)
{
struct hostent *hent;
int iplen = 15; //XXX.XXX.XXX.XXX
char *ip = (char *)malloc(iplen+1);
memset(ip, 0, iplen+1);
if((hent = gethostbyname(host)) == NULL)
{
herror("Can't get IP");
exit(1);
}
if(inet_ntop(AF_INET, (void *)hent->h_addr_list[0], ip, iplen) == NULL)
{
perror("Can't resolve host");
exit(1);
}
return ip;
}
char *build_get_query(char *host, char *page)
{
char *query;
char *getpage = page;
char *tpl = "GET /%s HTTP/1.0\r\nHost: %s\r\nUser-Agent: %s\r\n\r\n";
if(getpage[0] == '/'){
getpage = getpage + 1;
fprintf(stderr,"Removing leading \"/\", converting %s to %s\n", page, getpage);
}
// -5 is to consider the %s %s %s in tpl and the ending \0
query = (char *)malloc(strlen(host)+strlen(getpage)+strlen(USERAGENT)+strlen(OS)+strlen(tpl)-5);
sprintf(query, tpl, getpage, host, USERAGENT);
return query;
// FILE *f;
// f = fopen(HTMLfile, "w");
// fprintf(f, htmlcontent);
// fclose(f);
}
这是我保存文件的位置:
FILE *f;
f = fopen(HTMLfile, "w");
fprintf(f, "%s", htmlcontent); //stderr, "%s"
fclose(f);
这是它为我的问题保存的结果(此页面)
(['_setCustomVar', 1, 'tags', '|c|file|networking|']);
_gaq.push(['_trackPageview']);
var _qevents = _qevents || [];
(function () {
var ssl='https:'==document.location.protocol,
s=document.getElementsByTagName('script')[0],
ga=document.createElement('script');
ga.type='text/javascript';
ga.async=true;
ga.src=(ssl?'https://ssl':'http://www')+'.google-analytics.com/ga.js';
s.parentNode.insertBefore(ga,s);
var sc=document.createElement('script');
sc.type='text/javascript';
sc.async=true;
sc.src=(ssl?'https://secure':'http://edge')+'.quantserve.com/quant.js';
s.parentNode.insertBefore(sc,s);
})();
_qevents.push({ qacct: "p-c1rF4kxgLUzNc" });
</script>
</body>
</html>