麻烦诸位帮忙跑个程序

水星

下面的程序是有关进程调度的，程序试图将一个普通进程赋予较高的优先级。

1. 
   
2. #include <string.h>
   
3. #include <stdio.h>
   
4. #include <errno.h>
   
5. #include <unistd.h>
   
6. #include <sys/types.h>
   
7. #include <sys/time.h>
   
8. #include <sys/resource.h>
   
9. #include <sched.h>
   
10. 
    
11. int main()
    
12. {
    
13.     uid_t iUID;
    
14.     struct sched_param sSchedParam;
    
15.     struct rlimit * psLimit;
    
16. 
    
17.     iUID = getuid();
    
18.     setuid(0);
    
19. 
    
20.     getrlimit(RLIMIT_NICE, psLimit);
    
21.     printf("struct rlimit: rlim_cur = %d, rlim_max = %d\n", psLimit->rlim_cur, psLimit->rlim_max);
    
22.     if(psLimit->rlim_max == 0)
    
23.     {
    
24.         psLimit->rlim_max = -1;
    
25.         if(setrlimit(RLIMIT_NICE, psLimit) != 0)
    
26.             printf("Failed to setrlimit: %s\n", strerror(errno));
    
27.     }
    
28. 
    
29.     sSchedParam.sched_priority = 1;
    
30.     if (sched_setscheduler(0, SCHED_FIFO, &sSchedParam) == -1)
    
31.     {
    
32.         printf("Failed to set scheduling parameters: %s\n", strerror(errno));
    
33.     }
    
34.     setuid(iUID);
    
35. }
    

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在我的系统中的执行结果：

1. 
   
2. struct rlimit: rlim_cur = 0, rlim_max = 0
   
3. Failed to setrlimit: Operation not permitted
   
4. Failed to set scheduling parameters: Operation not permitted
   

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从网上搜到有的系统(ubuntu)的rlim_max = -1，因此没有Operation not permitted那项。

麻烦哪位好心人把系统情况和运行输出告诉我。谢谢！

我的系统：

1. 
   
2. $ uname -a
   
3. Linux RAYS 2.6.17-2-686 #2 SMP Mon Aug 28 15:33:43 CST 2006 i686 GNU/Linux
   

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信天游

运行结果：

2. [aaron@localhost tcp]$ ./helpshuixin
3. struct rlimit: rlim_cur = 1474660693, rlim_max = -326937770
4. Failed to set scheduling parameters: Operation not permitted
5. [aaron@localhost tcp]$ uname -a
6. Linux localhost.localdomain 2.6.15-1.2054_FC5 #1 Tue Mar 14 15:48:33 EST 2006 i686 i686 i386 GNU/Linux
7. [aaron@localhost tcp]$
8.    

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DoDo

1. 
   
2. rf@debian:~/shm$ gcc t.c
   
3. rf@debian:~/shm$ ./a.out
   
4. struct rlimit: rlim_cur = 18589, rlim_max = 85472
   
5. Failed to set scheduling parameters: Operation not permitted
   

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但若用 root 执行则不会错误

1. 
   
2. rf@debian:~/shm$ uname -a
   
3. Linux debian 2.6.18 #1 Sun Feb 25 01:37:19 CST 2007 i686 GNU/Linux
   

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水星

谢谢二位，我再好好研究研究

dajun

you need to be root to run this programm :cool: