Linux内核的ioctl函数学习2 - linux系统ioctl使用示例

#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include <errno.h>
#include <unistd.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <sys/ioctl.h>
#include <net/if.h>

static void usage(){
printf("usage : ipconfig interface /n");
exit(0);
}

int main(int argc,char **argv)
{
struct sockaddr_in *addr;
struct ifreq ifr;
char *name,*address;
int sockfd;
if(argc != 2)
usage();
else
name = argv[1];
sockfd = socket(AF_INET,SOCK_DGRAM,0);
strncpy(ifr.ifr_name,name,IFNAMSIZ-1);
if(ioctl(sockfd,SIOCGIFADDR,&ifr) == -1)
perror("ioctl error"),exit(1);
addr = (struct sockaddr_in *)&(ifr.ifr_addr);
address = inet_ntoa(addr->sin_addr);
printf("inet addr: %s ",address);
if(ioctl(sockfd,SIOCGIFBRDADDR,&ifr) == -1)
perror("ioctl error"),exit(1);
addr = (struct sockaddr_in *)&ifr.ifr_broadaddr;
address = inet_ntoa(addr->sin_addr);
printf("broad addr: %s ",address);
if(ioctl(sockfd,SIOCGIFNETMASK,&ifr) == -1)
perror("ioctl error"),exit(1);
addr = (struct sockaddr_in *)&ifr.ifr_addr;
address = inet_ntoa(addr->sin_addr);
printf("inet mask: %s ",address);
printf("/n");
exit(0);
}

#include <stdio.h>
#include <string.h>
#include <errno.h>
#include <fcntl.h>
#include <getopt.h>
#include <sys/socket.h>
#include <sys/ioctl.h>
#include <net/if.h>
#include <stdlib.h>
#include <unistd.h>
typedef unsigned short u16;
typedef unsigned int u32;
typedef unsigned char u8;
#include <linux/ethtool.h>
#include <linux/sockios.h>
int detect_mii(int skfd, char *ifname)
{
struct ifreq ifr;
u16 *data, mii_val;
unsigned phy_id;
/* Get the vitals from the interface. */
strncpy(ifr.ifr_name, ifname, IFNAMSIZ);
if (ioctl(skfd, SIOCGMIIPHY, &ifr) < 0)
{
fprintf(stderr, "SIOCGMIIPHY on %s failed: %s/n", ifname,
strerror(errno));
(void) close(skfd);
return 2;
}
data = (u16 *)(&ifr.ifr_data);
phy_id = data[0];
data[1] = 1;
if (ioctl(skfd, SIOCGMIIREG, &ifr) < 0)
{
fprintf(stderr, "SIOCGMIIREG on %s failed: %s/n", ifr.ifr_name,
strerror(errno));
return 2;
}
mii_val = data[3];
return(((mii_val & 0x0016) == 0x0004) ? 0 : 1);
}
int detect_ethtool(int skfd, char *ifname)
{
struct ifreq ifr;
struct ethtool_value edata;
memset(&ifr, 0, sizeof(ifr));
edata.cmd = ETHTOOL_GLINK;
strncpy(ifr.ifr_name, ifname, sizeof(ifr.ifr_name)-1);
ifr.ifr_data = (char *) &edata;
if (ioctl(skfd, SIOCETHTOOL, &ifr) == -1)
{
printf("ETHTOOL_GLINK failed: %s/n", strerror(errno));
return 2;
}
return (edata.data ? 0 : 1);
}
int main(int argc, char **argv)
{
int skfd = -1;
char *ifname;
int retval;
if( argv[1] )
ifname = argv[1];
else
ifname = "eth0";
/* Open a socket. */
if (( skfd = socket( AF_INET, SOCK_DGRAM, 0 ) ) < 0 )
{
printf("socket error/n");
exit(-1);
}
retval = detect_ethtool(skfd, ifname);
if (retval == 2)
retval = detect_mii(skfd, ifname);
close(skfd);
if (retval == 2)
printf("Could not determine status/n");
if (retval == 1)
printf("Link down/n");
if (retval == 0)
printf("Link up/n");
return retval;
}

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <errno.h>
#include <net/if.h>
#include <linux/sockios.h>
#include <sys/ioctl.h>
#define LINKTEST_GLINK 0x0000000a
struct linktest_value {
unsigned int    cmd;
unsigned int    data;
};

static
void
usage(const char * pname)
{
fprintf(stderr, "usage: %s <device>/n", pname);
fprintf(stderr, "returns: /n");
fprintf(stderr, "/t 0: link detected/n");
fprintf(stderr, "/t%d: %s/n", ENODEV, strerror(ENODEV));
fprintf(stderr, "/t%d: %s/n", ENONET, strerror(ENONET));
fprintf(stderr, "/t%d: %s/n", EOPNOTSUPP, strerror(EOPNOTSUPP));
exit(EXIT_FAILURE);
}

static
int
linktest(const char * devname)
{
struct ifreq ifr;
struct linktest_value edata;
int fd;
/* setup our control structures. */
memset(&ifr, 0, sizeof(ifr));
strcpy(ifr.ifr_name, devname);
/* open control socket. */
fd=socket(AF_INET, SOCK_DGRAM, 0);
if(fd < 0 ) {
return -ECOMM;
}
errno=0;
edata.cmd = LINKTEST_GLINK;
ifr.ifr_data = (caddr_t)&edata;
if(!ioctl(fd, SIOCETHTOOL, &ifr)) {
if(edata.data) {
fprintf(stdout, "link detected on %s/n", devname);
return 0;
} else {
errno=ENONET;
}
}
perror("linktest");
return errno;
}

int
main(int argc, char *argv[])
{
if(argc != 2) {
usage(argv[0]);
}
return linktest(argv[1]);
}

#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <sys/ioctl.h>
#include <sys/soundcard.h>
#include <stdio.h>
#include <unistd.h>
#include <math.h>
#include <string.h>
#include <stdlib.h>
#define  BASE_VALUE 257
int main(int argc,char *argv[])
{
int mixer_fd=0;
char *names[SOUND_MIXER_NRDEVICES]=SOUND_DEVICE_LABELS;
int value,i;
printf("/nusage:%s dev_no.[0..24] value[0..100]/n/n",argv[0]);
printf("eg. %s 0 100/n",argv[0]);
printf("    will change the volume to MAX volume./n/n");
printf("The dev_no. are as below:/n");
for (i=0;i<SOUND_MIXER_NRDEVICES;i++){
if (i%3==0) printf("/n");
printf("%s:%d/t/t",names[i],i);
}
printf("/n/n");
if (argc<3)
exit(1);
if ((mixer_fd = open("/dev/mixer",O_RDWR))){
printf("Mixer opened successfully,working.../n");
value=BASE_VALUE*atoi(argv[2]);
if (ioctl(mixer_fd,MIXER_WRITE(atoi(argv[1])),&value)==0)
printf("successfully.....");
else    printf("unsuccessfully.....");
printf("done./n");
}else
printf("can't open /dev/mixer error..../n");
exit(0);
}