これは私のプログラムです：
int main(int argc, char *argv[]){
if(argc != 2){
printf("Uso: ./server <numero porta>\n");
exit(1);
}
int sockd, newsockd, LunghezzaClient;
int NumPorta = atoi(argv[1]);
struct sockaddr_in serv_addr, cli_addr; /* indirizzo del server e del client */
int rc, fd;
off_t offset = 0;
struct stat stat_buf;
char filename[1024] = {};
size_t fsize;
if((sockd = socket(AF_INET, SOCK_STREAM, 0)) < 0){
perror("Errore creazione socket\n");
exit(EXIT_FAILURE);
}
bzero((char *) &serv_addr, sizeof(serv_addr)); /* bzero scrive dei null bytes dove specificato per la lunghezza specificata */
serv_addr.sin_family = AF_INET; /* la famiglia dei protocolli */
serv_addr.sin_port = htons(NumPorta); /* porta htons converte nell'ordine dei byte di rete */
serv_addr.sin_addr.s_addr = INADDR_ANY; /* dato che è un server bisogna associargli l'indirizzo della macchina su cui sta girando */
if(bind(sockd, (struct sockaddr *) &serv_addr, sizeof(serv_addr)) < 0){
perror("Errore di bind\n");
onexit(NULL, sockd, NULL, 1);
}
if(listen(sockd, 5) < 0){
perror("Errore nella funzione listen");
onexit(NULL, sockd, NULL, 1);
}
LunghezzaClient = sizeof(cli_addr);
signal (SIGINT, ( void *)sig_handler);
while(1){
if((newsockd = accept(sockd, (struct sockaddr *) &cli_addr, (socklen_t *) &LunghezzaClient)) < 0){
perror("Errore nella connessione\n");
onexit(newsockd, sockd, NULL, 2);
}
/* get the file name from the client */
if((rc = recv(newsockd, filename, sizeof(filename), 0)) < 0){
perror("Errore nella ricezione del nome del file");
onexit(newsockd, sockd, NULL, 2);
}
/* Terminiamo il nome del file con NULL e se ultimo carattere è \n o \r lo cambiamo con \0*/
filename[rc] = '\0';
if (filename[strlen(filename)-1] == '\n')
filename[strlen(filename)-1] = '\0';
if (filename[strlen(filename)-1] == '\r')
filename[strlen(filename)-1] = '\0';
/* inet_ntoa converte un hostname in un ip decimale puntato */
fprintf(stderr, "Ricevuta richiesta di inviare il file '%s' dall' indirizzo %s\n", filename, inet_ntoa(cli_addr.sin_addr));
/* open the file to be sent */
fd = open(filename, O_RDONLY);
if (fd < 0) {
fprintf(stderr, "Impossibile aprire '%s': %s\n", filename, strerror(errno));
onexit(newsockd, sockd, NULL, 2);
}
/* get the size of the file to be sent */
if(fstat(fd, &stat_buf) < 0){
perror("Errore fstat");
onexit(newsockd, sockd, fd, 3);
}
fsize = stat_buf.st_size;
if(send(newsockd, &fsize, sizeof(fsize), 0) < 0){
perror("Errore durante l'invio della grandezza del file\n");
onexit(newsockd, sockd, fd, 3);
}
/* copy file using sendfile */
offset = 0;
rc = sendfile(newsockd, fd, &offset, stat_buf.st_size);
if (rc == -1) {
fprintf(stderr, "Errore durante l'invio di: '%s'\n", strerror(errno));
onexit(newsockd, sockd, fd, 3);
}
if (rc != fsize) {
fprintf(stderr, "Trasferimento incompleto: %d di %d bytes\n", rc, (int)stat_buf.st_size);
onexit(newsockd, sockd, fd, 3);
}
onexit(newsockd, NULL, fd, 4);
}
close(sockd);
exit(EXIT_SUCCESS);
}
しかし、それをコンパイルしようとすると、機能に間違いが多すぎるために多くの警告が表示されgcc -Wall -O3 -o program myprogram.cましたonexit。これが私が得た警告です：
server-iterativo.c: In function ‘main’:
server-iterativo.c:51:3: warning: passing argument 1 of ‘onexit’ makes integer from pointer without a cast [enabled by default]
server-iterativo.c:23:6: note: expected ‘int’ but argument is of type ‘void *’
server-iterativo.c:56:7: warning: passing argument 1 of ‘onexit’ makes integer from pointer without a cast [enabled by default]
server-iterativo.c:23:6: note: expected ‘int’ but argument is of type ‘void *’
server-iterativo.c:92:7: warning: passing argument 3 of ‘onexit’ makes pointer from integer without a cast [enabled by default]
server-iterativo.c:23:6: note: expected ‘struct FILE *’ but argument is of type ‘int’
server-iterativo.c:97:7: warning: passing argument 3 of ‘onexit’ makes pointer from integer without a cast [enabled by default]
server-iterativo.c:23:6: note: expected ‘struct FILE *’ but argument is of type ‘int’
server-iterativo.c:104:9: warning: passing argument 3 of ‘onexit’ makes pointer from integer without a cast [enabled by default]
server-iterativo.c:23:6: note: expected ‘struct FILE *’ but argument is of type ‘int’
server-iterativo.c:108:9: warning: passing argument 3 of ‘onexit’ makes pointer from integer without a cast [enabled by default]
server-iterativo.c:23:6: note: expected ‘struct FILE *’ but argument is of type ‘int’
server-iterativo.c:111:3: warning: passing argument 2 of ‘onexit’ makes integer from pointer without a cast [enabled by default]
server-iterativo.c:23:6: note: expected ‘int’ but argument is of type ‘void *’
server-iterativo.c:111:3: warning: passing argument 3 of ‘onexit’ makes pointer from integer without a cast [enabled by default]
server-iterativo.c:23:6: note: expected ‘struct FILE *’ but argument is of type ‘int’
server-iterativo.c: In function ‘onexit’:
server-iterativo.c:131:3: warning: passing argument 1 of ‘close’ makes integer from pointer without a cast [enabled by default]
/usr/include/unistd.h:354:12: note: expected ‘int’ but argument is of type ‘struct FILE *’
server-iterativo.c:136:3: warning: passing argument 1 of ‘close’ makes integer from pointer without a cast [enabled by default]
/usr/include/unistd.h:354:12: note: expected ‘int’ but argument is of type ‘struct FILE *’
なぜこのエラーが発生したのか理解できません:(