Find the specified string value in the specified file

# Include <stdio. h>
# Include <unistd. h>
# Include <sys/types. h>
# Include <sys/STAT. h>
# Include <fcntl. h>
# Include <stdlib. h>
# Include <string. h>
# Include <Linux/kernel. h>

Static unsigned long get_file_size (const char * path)
{
Struct stat statbuff;
If (STAT (path, & statbuff)> = 0 ){
Return statbuff. st_size;
}
Return-1;
}

Static unsigned int print_network_name (void)
{
Int FD =-1;
Int size = 0;
Int I = 0;
Char Buf [100];
Char strbuf [100];
Char * P;
Unsigned long filesize = get_file_size ("./sets. conf ");
Char * buffer = (char *) malloc (filesize + 1 );
Char * tmpbuf = (char *) malloc (filesize + 1 );
If (null = buffer | null = tmpbuf)
{
Printf ("% s malloc error \ n", _ FUNC __);
Return-1;
}
FD = open ("./sets. conf", o_rdonly );
If (-1 = FD)
{
Printf ("% s open error \ n", _ FUNC __);
Return-1;
}
Size = read (FD, buffer, filesize );
If (size! = Filesize)
{
Printf ("% s Read File Len error \ n", _ FUNC __);
Close (FD );
Return-1;
}
Close (FD );

P = strstr (buffer, "networkdevice ");
Memcpy (tmpbuf, P, (unsigned INT) (P-buffer)/sizeof (char )));
P = strstr (tmpbuf, "devicename ");
P + = sizeof ("devicename ");
While (* P! = '\ N ')
{
Buf [I] = * P;
I ++;
P ++;
}
Buf [I] = '\ 0 ';

Free (buffer );
Free (tmpbuf );

Memset (strbuf, 0xff, 100 );
Sprintf (strbuf, "networkname: % s", Buf );
Printf ("% s \ n", strbuf );

Return 0;
}

Void main (void)

{

Print_network_name (();

}

Find the value of devicename in the [networkdevice] field of sets. conf.

[Networkdevice]
Connectednetwork = DHCP
Devicename = eth0