linux c 生成uuid

/********方法一**********/
#include <stdio.h>

#include <stdlib.h>

#include <string.h>

/**

 * Create random UUID

 *

 * @param buf - buffer to be filled with the uuid string

 */

char *random_uuid( char buf[37] )

{

	const char *c = "89ab";

    char *p = buf;

    int n;

    for( n = 0; n < 16; ++n )

    {

        int b = rand()%255;

        switch( n )

        {

            case 6:

                sprintf(p, "4%x", b%15 );

			break;

            case 8:

                sprintf(p, "%c%x", c[rand()%strlen(c)], b%15 );

            break;

            default:

                sprintf(p, "%02x", b);

            break;

        }



        p += 2;

        switch( n )

        {

            case 3:

            case 5:

            case 7:

            case 9:

                *p++ = '-';

                break;

        }

    }

    *p = 0;

    return buf;

}



void main()

{

	char guid[37];

	random_uuid(guid);

	printf("guid = %s\n", guid);

	random_uuid(guid);

	printf("guid = %s\n", guid);

	random_uuid(guid);

	printf("guid = %s\n", guid);

	random_uuid(guid);

	printf("guid = %s\n", guid);

}

　　运行如下：

daniel@debian:~/src$ gcc getuuid.c

daniel@debian:~/src$ ./a.out 

guid = a397a255-53be-41fc-996b-521413e9e22d

guid = 518e1f56-0857-49a7-a5d0-528277751b99

guid = 4aed583d-6a52-49d5-b668-8ead955f3c35

guid = b5c48cdd-6c11-453d-91b4-59cfce233d27

daniel@debian:~/src$ 

　

/********方法二**********/

/*libuuid是一个用于生成UUID的C库，具体用法参考http://linux.die.net/man/3/libuuid，示例如下：*/



#include <stdio.h>

#include <uuid/uuid.h>



int main(int argc, char **argv)

{

    uuid_t uuid;

    char str[36];



    uuid_generate(uuid);

    uuid_unparse(uuid, str);



    printf("%s\n", str);



    return 0;

}

在Linux下编译时需要链接uuid库



gcc -o uuid uuid.c -luuid

在Ubuntu中，可以用下面的命令安装libuuid：



sudo apt-get install uuid-dev