自定义shell只接受一个参数

所以我有一个shell的代码：

#include  #include  #define MAX_NUM_ARGS 256 #define SIZE 256 void orders(char *command[SIZE]); int main() { char buffer[SIZE]= ""; //char input_args[MAX_NUM_ARGS]; char **input_args = NULL; int i = 0;// counting variable int blah = 0; printf("Welcome to the AY shell.\n"); while(1){ //initialize array of strings //first free any prevously allocated memory if (input_args != NULL) { //memory has been allocated free it for (i = 0; i <MAX_NUM_ARGS; i++) { free(input_args[i]); } } //free array of strings free(input_args); //new allocate memory input_args = (char**) malloc(sizeof(char*) * MAX_NUM_ARGS); //check return value for error if (input_args == NULL) { printf("We are out of memory. =(\n"); continue; //print error: out of memory, exit with a error code exit(0); } //allocate memory for each string for (i = 0; i <MAX_NUM_ARGS; i++) { input_args[i]= (char*)malloc(sizeof(char) * MAX_NUM_ARGS); if(input_args[i] == NULL) {//error printf("Error, the input is empty."); continue; }//end of if statement }//end of for loop printf("~$: "); //prompts the user for input fgets(buffer, sizeof(buffer), stdin); //if the user types in exit, quit if (strcmp(buffer, "exit\n") == 0){ exit(0); } //end of if statement //if user types in clear, wipe the screen and repeat the lop else if(strcmp(buffer, "clear\n")==0){ system("clear"); continue; }//end of else if //should the user punch in nothing, repeat the loop else if (strcmp(buffer, "\n") == 0) { continue; }//end of else if input_args[1] = NULL; for (i = 0; i < SIZE; i++) { if(buffer[i] != '\n' && buffer[i] != ' ' && buffer[i] != '\t'){ input_args[0][i] = buffer[i]; } //end of if statement else{ input_args[0][i] = '\0'; }//end of else statment }//end of for loop //if the input doesn't fall under the conditionals above, execute orders. orders(input_args); } //end of while loop return 0; }//end of main function void orders(char *command[SIZE]){ //handles the commands of the shell int retval = 0; //return value int pid = 0; int childValue = 0; pid = fork(); if (pid != 0){ // printf("I'm the parent, waiting on the child.\n");//debug pid = waitpid(-1, &childValue,0); // printf("Child %d returned a value of %x in hex.\n", pid, childValue); return;//return backs to the main prompt }//end of if statement else{ // printf("I am the first child.\n"); retval = execvp(command[0], command); exit(2); if (retval != -1){ //print error! printf("Invalid command!\n"); exit(2); } }//end of else block }//end of orders function 

现在，它可以很好地执行clear，exit和单个单词命令，比如ls或pwd。 但是，诸如“vim”之类的多行命令不起作用，也不会更改目录。

我究竟做错了什么？

我怀疑retval = execvp（command [0]，command）; 造成问题，但我不太确定。 有什么想法吗？ 我不想直接回答，因为这是家庭作业，只是推动正确的方向。

Answer 1

这个部分：

 input_args[1] = NULL; for (i = 0; i < SIZE; i++) { if(buffer[i] != '\n' && buffer[i] != ' ' && buffer[i] != '\t'){ input_args[0][i] = buffer[i]; } //end of if statement else{ input_args[0][i] = '\0'; }//end of else statment }//end of for loop 

将input_args限制为仅使用第一个索引。 我假设你可以找到一种获得j++; 在else子句中使用input_args[j][i]或类似的东西......

你的最后一条评论与此匹配，因为你的retval = execvp(command[0], command); 也只使用列表中的第一项。