簡單shell實現
阿新 • • 發佈:2017-05-22
.net 執行 buffer 參數 tdi efi command 分開 結束
http://blog.csdn.net/lishuhuakai/article/details/11928055
#include <stdio.h> #include <unistd.h> #include <wait.h> #define MAXLINE 80 void setup (char inputBuffer[], char *argv[]) { int i, j; char *p; i = 0; for (p = inputBuffer; ;p++)/*將字符命令一段一段拆分開來,如輸入ls -l,則argv[0]= "ls",argv[1]="-l",argv[2]=NULL*/ { argv[i++] = p; while (*p != ‘ ‘ && *p != ‘\0‘) p++; if (*p == ‘\0‘) { break; } *p = ‘\0‘; } argv[i] = NULL;/*最後一個參數須用空指針NULL作結束*/ execvp (argv[0], argv);/*執行命令,argv[0]放著執行的命令,其余的argv放著參數*/ } int main() {char inputBuffer[MAXLINE]; char *argv[MAXLINE / 2 - 1]; while (1) { printf ("COMMAND->"); gets (inputBuffer);/*輸入命令*/ setup (inputBuffer, argv); printf ("撲街!"); } return 0; }
#include <stdio.h> #include <unistd.h> //#define SIZE 20#define MAXLINE 80 char *p; void setup (char inputBuffer[], char *argv[]) { int i, j; i = 0; for (p = inputBuffer; ;p++)/*一個一個地將輸入字符分開*/ { argv[i++] = p; while (*p != ‘ ‘ && *p != ‘\0‘) p++; if (*p == ‘\0‘) { break; } *p = ‘\0‘; } argv[i] = NULL; pid_t pid pid = fork();/*新建一個子進程*/ if (pid == 0)/*對於子進程,執行輸入的命令*/ { execvp (argv[0], argv); printf ("command not found\n");/*如果execvp執行失敗的話,會返回-1,也就是這句話會被執行*/ } else if( pid > 0 )/*對於父進程,等待*/ { wait(NULL);/*父進程等待子進程執行完*/ } else /*否則的話,就出錯了*/ { printf ("fork error\n"); } } int main() { char inputBuffer[MAXLINE]; char *argv[MAXLINE / 2 - 1]; while (1) { printf ("COMMAND->"); gets (inputBuffer); /*關於scanf和gets,scanf對於輸入的字符遇到空格或回車就結束了,而gets對於輸入的空格也接受*/ setup (inputBuffer, argv); } return 0; }
簡單shell實現