实验一：熟悉Linux命令.doc

操作系统实验报告实验一：熟悉Linux命令一、 实验目的熟悉Linux系统，掌握Linux系统的登入、退出等操作；熟悉Linux命令及进程管理；学会使用Linux下C语言编程的基本知识；二、 实验内容1、Linux基本操作2、文件与目录操作3、进程查看及在线帮助4、全屏幕文本编辑器Vi的熟悉5、Linux下C语言编程基础知识三、 代码及运行结果分析1、Linux基本操作，Linux系统的登入1.文件与目录的基本操作显示文件目录命令ls改变当前目录命令cd 建立子目录mkdir 删除子目录命令rmdir 删除文件命令rm文件改名命令mv文件复制命令cp 2、进程查看命令进程查看who命令ps命令top命令4、在线帮助联机帮助man命令联机帮助help命令whereis命令查看ls命令所在位置5、全屏幕文本编辑器Vi及Linux下C语言基础编程1)e06620208localhost e06620208$ vi sj.c#includeint main()printf(helloworld);return 0;:sj.c New 6L, 65C writtene06620208localhost e06620208$ gcc sj.c -o sje06620208localhost e06620208$ ./sjhelloworlde06620208localhost e06620208$2)e06620208localhost e06620208$ vi sjj.c#includemain() printf(The current process ID is %dn,getpid();sjj.c New 5L, 83C writtene06620208localhost e06620208$ gcc sjj.c -o sjje06620208localhost e06620208$ ./sjjThe current process ID is 24189e06620208localhost e06620208$ vi 1.c#include#includemain()pid_t pid;pid=fork();if(pid0)printf(error in fork!);else if(pid=0)printf(I am the child process, my process ID is %dn,getpid();elseprintf(I am the parent process, my process ID is %d %dn,getpid(),pid);1.c New 17L, 290C writtene06620208localhost e06620208$ gcc 1.c -o 11.c:10:24: warning: multi-line string literals are deprecated1.c:14:24: warning: multi-line string literals are deprecatede06620208localhost e06620208$ ./1I am the child process, my process ID is 23906I am the parent process, my process ID is 2390523906分析：fork被调用一次，能够返回两次，它可能有三种不同的返回值：1.在父进程中，fork返回新创建子进程的进程ID； 2.在子进程中，fork返回0；3.如果出现错误，fork返回一个负值；pid=fork();当pid0时，说明出现问题；当pid=0时，此时是子进程，返回的是0；否则，此时进行的是父进程，返回的是新创建的子进程的ID值。3)e06620208localhost e06620208$ vi jj.c#includemain()printf(this process will exit!n);exit(0);printf(never be displayed!n); jj.c New 7L, 114C writtene06620208localhost e06620208$ gcc jj.c -o jje06620208localhost e06620208$ ./jjthis process will exit!分析:程序运行到exit(0);时将退出printf();语句不执行，程序最终输出this process will exit!4)e06620208localhost e06620208$ vi jjj.c#include #include main()pid_t pid;pid=fork();if(pid0)printf(error occurred!n);else if(pid=0) exit(0);elsesleep(10);wait(NULL);jjj.c New 14L, 189C writtene06620208localhost e06620208$ gcc jjj.c -o jjje06620208localhost e06620208$ ./jjj &1 24906e06620208localhost e06620208$ vi jjje.c#include #include #include #include main()pid_t pc,pr;pc=fork();if(pc0) printf(error ocurred!n);else if(pc=0)printf(This is child process with pid of %dn,getpid();sleep(10);elsepr=wait(NULL);printf(I catched a child process with pid of %dn,pr);exit(0); e.c New 21L, 366C written1+ exit 75 ./jjje06620208localhost e06620208$ gcc e.c -o ee06620208localhost e06620208$ ./eThis is child process with pid of 25120I catched a child process with pid of 25120实验二：进程管理一、实验目的加深对进程概念的理解，明确进程和程序的区别；进一步认识并发执行的实质；分析进程争用资源的现象，学习解决进程互斥的方法。 二、实验内容1、运行以下附录部分中给出的程序，查看自己运行的结果，并进行分析 2、编写程序，要求见附录部分三、代码及运行结果分析1)新建文件s1.c，并输入程序e06620208localhost e06620208$ vi s1.c#include stdio.hmain()int i,j,k;if (i=fork()j=wait();printf(Parent Process!n);printf(i=%d,j=%d,k=%dn,i,j);elsek=getpid();printf(Child Process!n);printf(i=%d,k=%dnn,i,k);进程号s1.c New 14L, 208C writtene06620208localhost e06620208$ gcc s1.c -o s1i=252252522525e06620208localhost e06620208$ ./s1Child Process!i=0,k=25225i=025225Parent Process!i=25225,j=25225,k=134513639分析：程序1运行后，i为0，程序执行else语句，k=0，输出两个语句中的内容，i=25225，执行if语句中内容，程序输出父进程的ID等，程序执行的进程树如右所示：2)e06620208localhost e06620208$ vi s2.c#includemain()int p1,p2;while(p1=fork()=-1); if(p1=0) printf(b.My process ID is %d,getpid();else while(p2=fork()=-1); if(p2=0) printf(c.My process ID is %d,getpid();else printf(a.My process ID is %d,getpid();s2.c New 15L, 279C writtene06620208localhost e06620208$ gcc s2.c -o s2e06620208localhost e06620208$ ./s2b.My process ID is 25425c.My process ID is 25426a.My process ID is 25424e06620207localhost e06620208$分析：程序2运行，满足p1=0，输出父进程ID，p1=fork()，p1值发生改变，else条件满足，之后再判断p2的值同样输出子进程的ID，最后输出下级子进程的ID，运行结果如上。程序执行后其进程树如下：p1=25425,p2=25426p1=25425,p2=0p1=0,p2=02542625425254243)e06620208localhost e06620208$ vi s3.c#includemain()int m,n,k;m=fork();printf(PID:%dt,getpid();printf(The return value of fork():%dtt,m);printf(hen);n=fork();printf(PID:%dt,getpid();printf(The return value of fork():%dtt,n);printf(han);k=fork();printf(PID:%dt,getpid();printf(The return value of fork():%dtt,k);printf(hon);s3.c New 17L, 347C writtene06620208localhost e06620208$ gcc s3.c -o s3e06620208localhost e06620208$ ./s3PID:25580 The return value of fork():0 hePID:25581 The return value of fork():0 haPID:25582 The return value of fork():0 hoPID:25581 The return value of fork():25582 hoPID:25580 The return value of fork():25581 haPID:25579 The return value of fork():25580 hePID:25584 The return value of fork():0 haPID:25579 The return value of fork():25584 haPID:25586 The return value of fork():0 hoPID:25579 The return value of fork():25586 hoe06620208localhost e06620208$ PID:25583 The return value of fork():0 hoPID:25580 The return value of fork():25583 hoPID:25585 The return value of fork():0 hoPID:25584 The return value of fork():25585 ho分析：产生进程树如图所示：m=25580,n=25581,k=2558225579k=0m=0,n=25584,k=25585255822558025581n=0,k=25583n=0,k=25586255811255822558225582k=0k=0k=04）e06620208localhost e06620208$ vi s4.c#includemain()int p1,p2,i;while(p1=fork()=-1);if(p1=0)for(i=0;i10;i+)printf(son%dn,i);elsewhile(p2=fork()=-1);if(p2=0)for(i=0;i10;i+)printf(daughter%dn,i);elsefor(i=0;i10;i+)printf(parent%dn,i);s4.c New 19L, 250C writtene06620208localhost e06620208$ gcc s4.c -o s4e06620208localhost e06620208$ ./s4son0son1son2son3son4son5son6son7son8son9son10daughter0daughter1daughter2daughter3daughter4daughter5daughter6daughter7daughter8daughter9daughter10parent0parent1parent2parent3parent4parent5parent6parent7parent8parent9parent10分析：运行结果如上所示。2、编写程序，程序运行时，系统中存在要求的进程树结构e06620208localhost e06620208$ vi s5.c#includemain()int m,n,k;m=fork();printf(PID:%dt,getpid();printf(The return value of fork():%dtt,m);printf(hen);n=fork();printf(PID:%dt,getpid();printf(The return value of fork():%dtt,n);printf(han);k=fork();if(m0&n0)printf(PID:%dt,getpid();printf(The return value of fork():%dtt,k);printf(hon);s5.c New 19L, 363C writtene06620208localhost e06620208$ gcc s5.c -o s5e06620208localhost e06620208$ ./s5PID:25979 The return value of fork():0 hePID:25978 The return value of fork():25979 hePID:25981 The return value of fork():0 haPID:25978 The return value of fork():25981 haPID:25983 The return value of fork():0 hoPID:25978 The return value of fork():25983 hoe06620208localhost e06620208$ PID:25980 The return value of fork():0 haPID:25979 The return value of fork():25980 ha分析：设置if(m0&n0)2、对以上程序4进行修改，使得修改以后的程序在运行过程中三个进程不会被