实现ping功能，就肯定要用到ping命令，那么在Linux下ping命令为：
ping [-dfnqrRv][-c<完成次数>][-i<间隔秒数>][-I<网络界面>][-l<前置载入>][-p<范本样式>][-s<数据包大小>][-t<存活数值>][主机名称或IP地址]
ping命令说明
PING() System Manager's Manual: iputils PING(8)
NAME
ping, ping6 - send ICMP ECHO_REQUEST to network hosts
SYNOPSIS
ping [-LRUbdfnqrvVaAB] [-c count] [-m mark] [-i interval] [-l preload]
[-p pattern] [-s packetsize] [-t ttl] [-w deadline] [-F flowlabel] [-I
interface] [-M hint] [-N nioption] [-Q tos] [-S sndbuf] [-T timestamp
option] [-W timeout] [hop ...] destination
ping [-dfnqrRv][-c<完成次数>][-i<间隔秒数>][-I<网络界面>][-l<前置载入>]
[-p<范本样式>][-s<数据包大小>][-t<存活数值>][主机名称或IP地址]
DESCRIPTION
ping uses the ICMP protocol's mandatory ECHO_REQUEST datagram to elicit
an ICMP ECHO_RESPONSE from a host or gateway. ECHO_REQUEST datagrams
(``pings'') have an IP and ICMP header, followed by a struct timeval
and then an arbitrary number of ``pad'' bytes used to fill out the
packet.
ping6 can also send Node Information Queries (RFC4620).
OPTIONS
-a Audible ping.
-b Allow pinging a broadcast address.允许ping一个广播地址
-B Do not allow ping to change source address of probes. The
address is bound to one selected when ping starts.
-m mark
use mark to tag the packets going out. This is useful for vari‐
ety of reasons within the kernel such as using policy routing to
select specific outbound processing.
-c count
Stop after sending count ECHO_REQUEST packets. With deadline
option, ping waits for count ECHO_REPLY packets, until the time‐
out expires.打印语句
-d Set the SO_DEBUG option on the socket being used. Essentially,
this socket option is not used by Linux kernel.
-F flow label
Allocate and bit flow label on echo request packets.
(Only ping6). If value is zero, kernel allocates random flow
label.
-f Flood ping. For every ECHO_REQUEST sent a period ``.'' is
printed, while for ever ECHO_REPLY received a backspace is
printed. This provides a rapid display of how many packets are
being dropped. If interval is not given, it sets interval to
zero and outputs packets as fast as they come back or one hun‐
dred times per second, whichever is more. Only the super-user
may use this option with zero interval.
-i interval
Wait interval seconds between sending each packet. The default
is to wait for one second between each packet normally, or not
to wait in flood mode. Only super-user may set interval to val‐
ues less 0.2 seconds.
-I interface address
Set source address to specified interface address. Argument may
be numeric IP address or name of device. When pinging IPv6 link-
local address this option is required.
-l preload
If preload is specified, ping sends that many packets not wait‐
ing for reply. Only the super-user may select preload more than
.
-L Suppress loopback of multicast packets. This flag only applies
if the ping destination is a multicast address.
-n Numeric output only. No attempt will be made to lookup symbolic
names for host addresses.
-p pattern
You may specify up to ``pad'' bytes to fill out the packet
you send. This is useful for diagnosing data-dependent problems
in a network. For example, -p ff will cause the sent packet to
be filled with all ones.
-D Print timestamp (unix time + microseconds as in gettimeofday)
before each line.
-q Quiet output. Nothing is displayed except the summary lines at
startup time and when finished.
-R Record route. Includes the RECORD_ROUTE option in the
ECHO_REQUEST packet and displays the route buffer on returned
packets. Note that the IP header is only large enough for nine
such routes. Many hosts ignore or discard this option.
-r Bypass the normal routing tables and send directly to a host on
an attached interface. If the host is not on a directly-
attached network, an error is returned. This option can be used
to ping a local host through an interface that has no route
through it provided the option -I is also used.
-s packetsize
Specifies the number of data bytes to be sent. The default is
, which translates into ICMP data bytes when combined with
the bytes of ICMP header data.
-S sndbuf
Set socket sndbuf. If not specified, it is selected to buffer
not more than one packet.
-t ttl Set the IP Time to Live.
-T timestamp option
Set special IP timestamp options. timestamp option may be
either tsonly (only timestamps), tsandaddr (timestamps and
addresses) or tsprespec host1 [host2 [host3 [host4]]] (timestamp
prespecified hops).
-U Print full user-to-user latency (the old behaviour). Normally
ping prints network round trip time, which can be different f.e.
due to DNS failures.
-v Verbose output.
-V Show version and exit.
-w deadline
Specify a timeout, in seconds, before ping exits regardless of
how many packets have been sent or received. In this case ping
does not stop after count packet are sent, it waits either for
deadline expire or until count probes are answered or for some
error notification from network.
-W timeout
Time to wait for a response, in seconds. The option affects only
timeout in absense of any responses, otherwise ping waits for
two RTTs.
那么用C语言实现ping过程如下：
#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include <errno.h>
#include <error.h>
#define error_exit(_errmsg) error(EXIT_FAILURE , errno, _errmsg)
int ping_ip(const char * ip)
{
FILE * fp = NULL;
] = {};
;
char * pstr = NULL;
] = {};
sprintf(_ip, "ping -c 1 %s > ./ping.txt",ip);
system("sudo touch ./ping.txt");
system("chmod 777 ./ping.txt");
system(_ip);
fp = fopen("./ping.txt","r");
if(fp == NULL)
{
error_exit("fopen");
}
, fp) > )
{
line++;
)
{
if((pstr = strstr(buffer, "64 bytes from")) != NULL)
{
while(strstr(pstr, "ttl=64"))
{
printf("net is ok\n");
;
}
}
else
{
printf("net is error\n");
;
}
}
memset(buffer, ,);
}
;
}
int main(int argc, const char *argv[])
{
ping_ip("192.168.123.24");
;
}