linux c模拟ls指令详解_

1、linux c模拟ls指令详解_ 本篇文章是对linux中基于c模拟ls指令的实现方法进行了具体的分析介绍，需要的伴侣参考下 代码如下: /* 模拟ls指令，实现参数-tariRl.有些代码重复消失，可改进 可以在该程序的基础上增加参数，该程序思路清楚，简单扩展 */ #includestdio.h #includestring.h #includestdlib.h #includesys/types.h #includeunistd.h #includesys/stat.h #includedirent.h #includesys/ioctl.h #includepwd.h #include

2、grp.h #define LL (10) /*带l参数标记*/ #define IL (11) /*带i参数标记*/ #define RU (12) /*带R参数标记*/ #define TL (116) /*带t参数标记*/ #define AL (117) /*带a参数标记*/ #define RL (118) /*带r参数标记*/ #define LENGTH 500 /*字符串最大长度*/ #define MAX_FILE_COUNT 500/*文件列表最大长度*/ /*函数声明*/ void error(char* error_message,int line); void dis

3、play(struct stat* stalist,char (*namelist)LENGTH,int n,int mode); int file_list(char* path,struct stat* stalist,char (*namelist)LENGTH,int mode); void display_simply(char (*namelist)LENGTH,int n); void display_LL(struct stat * stalist,char (*namelist)LENGTH,int n); void display_IL(struct stat * stal

4、ist,char (*namelist)LENGTH,int n); void display_LL_IL(struct stat * stalist,char (*namelist)LENGTH,int n); void display_RU(struct stat* stalist,char (*namelist)LENGTH,int n,int mode); void display_RU_LL(struct stat * stalist,char (*namelist)LENGTH,int n,int mode); void display_RU_IL(struct stat* sta

5、list,char (*namelist)LENGTH,int n,int mode); void display_RU_IL_LL(struct stat * stalist,char (*namelist)LENGTH,int n,int mode); /*主函数*/ int main(int argc,char *argv) int i,j; /*mode的前16个位用来标记那些能影响显示的参数，16位之后的位用来标记不影响输出格式的参数。这个程序只用到了0-3位，16-18位，假如要在该程序的基础上增加参数，可以用其他没有用法的位。 mode的第0位为1表示带l参数，mode的第1位为

6、1表示带i参数，mode的第2位为1表示带R参数，mode的第16位为1表示带t参数，mode的第17位为1表示带a参数，mode的第18位为1表示带r参数*/ int mode=0; char error_messageLENGTH=0;/*错误信息*/ char pathLENGTH=0;/*路径*/ struct stat stalistMAX_FILE_COUNT;/*文件具体信息数组*/ char namelistMAX_FILE_COUNTLENGTH;/*文件名数组*/ int flag=0;/*推断是否指定了名目*/ int count;/*文件个数*/ /*解析参数*/ fo

7、r(i=1;iargc;i+) if(argvi0=-)/*假如是选项参数*/ for(j=1;jstrlen(argvi);j+) if(argvij=l) mode=mode|LL; else if(argvij=i) mode=mode|IL; else if(argvij=R) mode=mode|RU; else if(argvij=r) mode=mode|RL; else if(argvij=a) mode=mode|AL; else if(argvij=t) mode=mode|TL; else snprintf(error_message,LENGTH,no option o

8、f %c,argvij); error(error_message,_LINE_); else/*参数为名目或文件*/ if(flag=1) error(can not specify more then two dir or file,_LINE_); else flag=1; if(argvi0!=/)/*相对路径*/ strcat(path,get_current_dir_name(); strcat(path,/); strncat(path,argvi,strlen(argvi); else/*肯定路径*/ strcpy(path,argvi); if(flag=0)/*未指定任何名

9、目或文件,则用法默认当前名目*/ strcat(path,get_current_dir_name(); /*依据mode猎取指定名目下的文件*/ count=file_list(path,stalist,namelist,mode); /*依据mode显示文件*/ display(stalist,namelist,count,mode); return 0; /*猎取文件列表*/ int file_list(char* path,struct stat* stalist,char (*namelist)LENGTH,int mode) int i=0,index,j,k; DIR *dir;

10、 struct dirent *ptr; char strLENGTH; char nametempLENGTH; struct stat statemp; if(stat(path,stalist0)0) / puts(path); error(the specify file is not exist,_LINE_); if(S_ISDIR(stalist0.st_mode)/*假如该路径指向的是一个名目*/ if(dir=opendir(path)=NULL)/*打开名目*/ sprintf(str,can not open %s,path); error(str,_LINE_); ch

11、dir(path);/*转变当前工作名目到path*/ i=0; while(ptr=readdir(dir)!=NULL)/*依次读取名目下的全部文件*/ if(ptr-d_name0=. !(mode AL)/*忽视隐蔽文件*/ continue; /*按字母挨次插入到stalist数组及namelist数组*/ for(j=i;j0;j-) if(strcmp(ptr-d_name,namelistj-1)0) break; for(k=i;kj;k-) strcpy(namelistk,namelistk-1); stalistk=stalistk-1; strcpy(namelist

12、j,ptr-d_name); stat(ptr-d_name,stalistj); i+; if(i=MAX_FILE_COUNT) error(file count beyond MAX_FILE_COUNT,_LINE_); closedir(dir); else j=strlen(path)-1; while(j=0 pathj!=/) j-; if(j0) error(path error,_LINE_); j+; k=0; while(pathj) namelist0k=pathj; j+; k+; namelist0k=0; return 1; if(mode TL)/*按文件修改

13、时间排序*/ for(j=0;ji;j+) index=j; for(k=j+1;ki;k+) if(stalistindex.st_mtimestalistk.st_mtime) index=k; statemp=stalistj; stalistj=stalistindex; stalistindex=statemp; strcpy(nametemp,namelistj); strcpy(namelistj,namelistindex); strcpy(namelistindex,nametemp); if(mode RL)/*反序排列*/ for(j=0;ji/2;j+) strcpy(

14、nametemp,namelistj); strcpy(namelistj,namelisti-j-1); strcpy(namelisti-j-1,nametemp); statemp=stalistj; stalistj=stalisti-j-1; stalisti-j-1=statemp; return i; /*依据mode选择不同的函数进行显示*/ void display(struct stat* stalist,char (*namelist)LENGTH,int n,int mode) /*使mode的高16位为0*/ int m = mode (116)-1); switch

15、(m) case 0: display_simply(namelist,n); break; case 1: display_LL(stalist,namelist,n); break; case 2: display_IL(stalist,namelist,n); break; case 3: display_LL_IL(stalist,namelist,n); break; case 4: display_RU(stalist,namelist,n,mode); break; case 5: display_RU_LL(stalist,namelist,n,mode); break; ca

16、se 6: display_RU_IL(stalist,namelist,n,mode); break; case 7: display_RU_IL_LL(stalist,namelist,n,mode); break; /*不带显示选项，简洁显示文件名*/ void display_simply(char (*namelist)LENGTH,int n) int i,maxlength=0,cols; struct winsize ts; for(i=0;in;i+) if(strlen(namelisti)maxlength) maxlength=strlen(namelisti); /*

17、猎取终端的大小*/ ioctl(STDIN_FILENO,TIOCGWINSZ,ts); cols=ts.ws_col; cols/=(maxlength+1); /lines=ts.ws_row; for(i=0;in;i+) if(i!=0 i%cols=0) puts(); printf(%*s,-(maxlength+1),namelisti); putchar(n); /*-l 参数，显示具体文件信息*/ void display_LL(struct stat * stalist,char (*namelist)LENGTH,int n) int i,mode; char* str;

18、 for(i=0;in;i+) mode=stalisti.st_mode; if(S_ISDIR(mode) printf(d); else printf(-); if(mode (18) printf(r); else printf(-); if(mode (17) printf(w); else printf(-); if(mode (16) printf(x); else printf(-); if(mode (15) printf(r); else printf(-); if(mode (14) printf(w); else printf(-); if(mode (13) prin

19、tf(x); else printf(-); if(mode (12) printf(r); else printf(-); if(mode (11) printf(w); else printf(-); if(mode (10) printf(x); else printf(-); printf( %-3d,stalisti.st_nlink); printf( %-6s,getpwuid(stalisti.st_uid)-pw_name); printf( %-6s,getgrgid(stalisti.st_gid)-gr_name); printf( %-10d,stalisti.st_

20、size); str=ctime(stalisti.st_mtime); strstrlen(str)-2=0; printf( %s,str); printf( %sn,namelisti); /*-i 参数，显示文件名及节点号*/ void display_IL(struct stat* stalist,char (*namelist)LENGTH,int n) int i,maxlength=0,cols; struct winsize ts; for(i=0;in;i+) if(strlen(namelisti)maxlength) maxlength=strlen(namelisti

21、); /*猎取终端的大小*/ ioctl(STDIN_FILENO,TIOCGWINSZ,ts); cols=ts.ws_col; cols/=(maxlength+9); /lines=ts.ws_row; for(i=0;in;i+) if(i!=0 i%cols=0) puts(); printf(%-8d ,stalisti.st_ino); printf(%*s,-(maxlength+1),namelisti); putchar(n); /*-li 参数，显示具体文件信息和节点号*/ void display_LL_IL(struct stat * stalist,char (*n

22、amelist)LENGTH,int n) int i,mode; char* str; for(i=0;in;i+) printf(%-8d ,stalisti.st_ino); mode=stalisti.st_mode; if(S_ISDIR(mode) printf(d); else printf(-); if(mode (18) printf(r); else printf(-); if(mode (17) printf(w); else printf(-); if(mode (16) printf(x); else printf(-); if(mode (15) printf(r)

23、; else printf(-); if(mode (14) printf(w); else printf(-); if(mode (13) printf(x); else printf(-); if(mode (12) printf(r); else printf(-); if(mode (11) printf(w); else printf(-); if(mode (10) printf(x); else printf(-); printf( %-3d,stalisti.st_nlink); printf( %-6s,getpwuid(stalisti.st_uid)-pw_name);

24、printf( %-6s,getgrgid(stalisti.st_gid)-gr_name); printf( %-10d,stalisti.st_size); str=ctime(stalisti.st_mtime); strstrlen(str)-2=0; printf( %s,str); printf( %sn,namelisti); /*-R 参数，简洁显示全部文件，包括名目下面的子名目*/ void display_RU(struct stat* stalist,char (*namelist)LENGTH,int n,int mode) int i,count; char pat

25、hLENGTH=0,tempLENGTH=0; struct stat staMAX_FILE_COUNT; char nameMAX_FILE_COUNTLENGTH; puts(get_current_dir_name(); display_simply(namelist,n); putchar(n); strcpy(path,get_current_dir_name(); for(i=0;in;i+) if(strcmp(namelisti,.)=0 | strcmp(namelisti,.)=0) continue; if(S_ISDIR(stalisti.st_mode) strcp

26、y(temp,path); strcat(path,/); strcat(path,namelisti); count=file_list(path,sta,name,mode); display_RU(sta,name,count,mode); strcpy(path,temp); /*-Rl 参数，显示全部文件，包括名目下面的子名目的具体信息*/ void display_RU_LL(struct stat * stalist,char (*namelist)LENGTH,int n,int mode) int i,count; char pathLENGTH=0,tempLENGTH=0

27、; struct stat staMAX_FILE_COUNT; char nameMAX_FILE_COUNTLENGTH; puts(get_current_dir_name(); display_LL(stalist,namelist,n); putchar(n); strcpy(path,get_current_dir_name(); for(i=0;in;i+) if(strcmp(namelisti,.)=0 | strcmp(namelisti,.)=0) continue; if(S_ISDIR(stalisti.st_mode) strcpy(temp,path); strc

28、at(path,/); strcat(path,namelisti); count=file_list(path,sta,name,mode); display_RU_LL(sta,name,count,mode); strcpy(path,temp); /*-Ri 参数，简洁显示全部文件，包括名目下的子名目，及节点号*/ void display_RU_IL(struct stat* stalist,char (*namelist)LENGTH,int n,int mode) int i,count; char pathLENGTH=0,tempLENGTH=0; struct stat staMAX_FILE_COUNT; char nameMAX_FILE_COUNTLENGTH; puts(get_current_dir_name(); display_IL(stalist,namelist,n); putchar(n); strcpy(path,get_current_dir_name(); for(i=0;in;i+) if(strcmp(namelisti,.)=0 | strcmp(namelist