w.rar_dos命令_拷贝文件 _文件删除拷贝

#include <stdio.h> #include <stdlib.h> #include <string.h> #define MAXSIZE 100 static char * usercmd[] = {"dir","cop","era","dis","end"}; static char * syscmd[] = {"ls -l","cp","rm -f","echo"}; static char * usage = "Welcome to use myshell, the follows are supported command\n" "dir -- show current directory and file\n" "cop file1 file2 -- copy file1 to file2 \n" "era file -- delete file\n" "dis string -- display string on screen\n" "end -- exit myshell \n" "NOTICE: Blank is avail before or after command\n"; int main(int argc, char * argv[]) { char *input=NULL; char *cmd=NULL,*para=NULL; char buf[MAXSIZE]; int i,count; input = malloc(MAXSIZE); cmd = malloc(MAXSIZE); para = malloc(MAXSIZE); if (input == NULL || cmd == NULL || para == NULL) { perror("malloc failed"); exit(-1); } while(1) { printf("myshell>"); fgets(input, 100, stdin); *(input+(strlen(input)-1)) = '\0';//delete '\n' while(*input != '\0') { if (*input != ' ' && *input != '\t') break; ++input; } if (*input == '\0')//all input is blank { printf("%s",usage); continue; } //division input to command and parameter parts count = strcspn(input, " \t"); strncpy(cmd, input, count); *(cmd + count) = '\0'; strncpy(para, input+count,strlen(input)-count); *(para+(strlen(input)-count))='\0'; if (0 == strcmp(cmd, usercmd[0])) { //根据这道题，分配的buf够用了，应该不会越界。 //如果要求很严格的话，这里用strncpy，strncat。 strcpy(buf,syscmd[0]); strcat(buf,para); system(buf); continue; } if (0 == strcmp(cmd, usercmd[1])) { strcpy(buf,syscmd[1]); strcat(buf,para); system(buf); continue; } if (0 == strcmp(cmd, usercmd[2])) { strcpy(buf,syscmd[2]); strcat(buf,para); system(buf); continue; } if (0 == strcmp(cmd, usercmd[3])) { strcpy(buf,syscmd[3]); strcat(buf,para); system(buf); continue; } if (0 == strcmp(cmd, usercmd[4])) { printf("Exit myshell\n"); break; } printf("%s",usage); } return 0; }