add libcurl example for fetching pop e and imap messages

examples/Makefile

@@ -0,0 +1,11 @@
+CPPFLAGS += -Wp,-MD,-MG
+CFLAGS += -g -Wall
+LIBS+= -lcurl
+
+all: fetchmail
+
+fetchmail: fetchmail.c
+	$(CC) $(LDFLAGS) -o $@ $? $(LIBS)
+
+clean:
+	rm -f *.o fetchmail

examples/fetchmail.c

@@ -0,0 +1,55 @@
+#include <stdio.h>
+
+#include <curl/curl.h>
+
+int main(int argc, char *argv[])
+{
+	char buf[128];
+	CURLcode res;
+	CURL *curl;
+	int use_pop = 1;
+
+	if (argc < 4) {
+		fprintf(stderr, "syntax %s <pop> <user> <pwd> [imap]\n",argv[0]);
+		return -1;
+	}
+
+	use_pop = (argc == 4);
+	curl = curl_easy_init();
+	if (!curl) {
+		fprintf(stderr, "can't init curl\n");
+		return -1;
+	}
+
+	/* Set username and password */
+	snprintf(buf, 128, "%s:%s", argv[2], argv[3]);
+	curl_easy_setopt(curl, CURLOPT_USERPWD, buf);
+
+	/* This will list every message of the given mailbox */
+	snprintf(buf, 128, "%ss://%s@%s/%s", use_pop? "pop3":"imap", argv[2], argv[1], use_pop?"":"INBOX");
+	printf("XXXX %s\n", buf);
+	curl_easy_setopt(curl, CURLOPT_URL, buf);
+
+	curl_easy_setopt(curl, CURLOPT_SSL_VERIFYPEER, 0L);
+	curl_easy_setopt(curl, CURLOPT_SSL_VERIFYHOST, 0L);
+
+	/* Perform the request, res will get the return code */ 
+	res = curl_easy_perform(curl);
+	/* Check for errors */ 
+	if(res != CURLE_OK)
+		fprintf(stderr, "curl_easy_perform() failed: %s\n",
+			  curl_easy_strerror(res));
+
+	snprintf(buf, 128, "%ss://%s@%s/%s1", use_pop? "pop3":"imap", argv[2], argv[1], use_pop?"":"INBOX;UID=");
+	printf("XXXX %s\n", buf);
+	curl_easy_setopt(curl, CURLOPT_URL, buf);
+	res = curl_easy_perform(curl);
+	/* Check for errors */ 
+	if(res != CURLE_OK)
+		fprintf(stderr, "curl_easy_perform() failed: %s\n",
+			  curl_easy_strerror(res));
+
+	/* always cleanup */ 
+	curl_easy_cleanup(curl);
+	return 0;
+}