c語言的curl 編程

[root @localhost 1105]# gcc -Wall -o curltest curltest.c
/tmp/ccosVANi.o: In function `main':
curltest.c:(.text+0x2a): undefined reference to `curl_easy_init'
curltest.c:(.text+0x53): undefined reference to `curl_easy_setopt'
curltest.c:(.text+0x5c): undefined reference to `curl_easy_perform'
curltest.c:(.text+0x68): undefined reference to `curl_easy_cleanup'

collect2: ld returned 1 exit status

解決辦法： gcc -Wall -o curltest curltest.c -l curl