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Hi, I am a beginner of unix system programming. So you see I have many problems in C and Unix. My programm can be run under rhel4, but can not under Fedora 8! It can show the detail of your current directory, just like "ls -l". I kind of suspect that it is the gcc that make this happen! Bacause I cant use char* and char[] correctly. It confuses me often. So is anybody has some ideas about this programm or you can teach me how to use char[] and char*? I know there are many hackers here! Thanks //This programm is to show the datail of your local directory #include<dirent.h> #include<stdio.h> #include<sys/types.h> #include<pwd.h> #include<sys/stat.h> #include<grp.h> #include<string.h> #include<time.h> void show_info( char *dirname ); void show_mode( int mode ); void myls3( char *dir ); int main(int argc,char *argv[]) { if (argc < 2) myls3("."); else { while(--argc) *++argv; myls3(*argv); // To ls the dir you input } } //open, read, and, close the directory void myls3( char *dir ) { DIR* dirptr; struct dirent* info; //open if( NULL == (dirptr = opendir(dir))) fprintf(stderr,"Cant open the dir %s\n",dir); //read while(NULL != (info = readdir(dirptr))) show_info(info->d_name); if(NULL == (info =(readdir(dirptr)))) fprintf(stderr,"Cant read the dir %s\n",dir);*/ closedir(dirptr); } //Show the details of the directory void show_info(char *dirname) { struct stat* dir_rec; if( -1 != stat( dirname,dir_rec ) ) { show_mode(dir_rec->st_mode); printf("%d ",dir_rec->st_nlink); printf("%2s ",getpwuid(dir_rec->st_uid)->pw_name); printf("%2s ",getgrgid(dir_rec->st_gid)->gr_name); printf("%d ",dir_rec->st_size); printf("%8s\n",ctime(&(dir_rec->st_ctime))+4); } } //This fuction transfer the mode of the directory into standard form void show_mode(int mode) { char *str; strcpy(str,"----------"); if(S_ISFIFO(mode)) str[0] = '-'; //Use the macro in <sys/stat.h> to determine the permission pattern if(S_ISDIR(mode)) str[0] = 'd'; if(S_ISCHR(mode)) str[0] = 'c'; if(S_ISBLK(mode)) str[0] = 'b'; if(S_IRUSR & mode) str[1] = 'r'; if(S_IWUSR & mode) str[2] = 'w'; if(S_IXUSR & mode) str[3] = 'x'; if(S_IRGRP & mode) str[4] = 'r'; if(S_IWGRP & mode) str[5] = 'w'; if(S_IXGRP & mode) str[6] = 'x'; if(S_IROTH & mode) str[7] = 'r'; if(S_IWOTH & mode) str[8] = 'w'; if(S_IXOTH & mode) str[9] = 'x'; printf("%s " , str); }

char *str; strcpy(str,"----------"); This is buggy. str should be an array of char, not a pointer. Read more about basic C programming. It should be char str[12]; // could be 10 strcpy(str,"---------");

-- Basile Starynkevitch http://starynkevitch.net/Basile/