このコードを使用していくつかのシェルコマンドを実行していますが、コマンドの後に終了しますls.: どこが間違っていますか?
#include <stdio.h>
#include <unistd.h>
#include <errno.h>
#define MAX_LINE 80 /* The maximum length command */
void setup(char inputBuffer[], char *args[],int *background)
{
int length, i, start, ct;
ct = 0;
/* read what the user enters on the command line */
length = read(STDIN_FILENO,inputBuffer,MAX_LINE);
start = -1;
if (length == 0)
exit(0); /* ^d was entered, end of user command stream */
if ( (length < 0) && (errno != EINTR) ) {
perror("error reading the command");
exit(-1); /* terminate with error code of -1 */
}
printf(">>%s<<",inputBuffer);
for (i=0;i<length;i++){ /* examine every character in the inputBuffer */
switch (inputBuffer[i]){
case ' ':
case '\t' : /* argument separators */
if(start != -1){
args[ct] = &inputBuffer[start]; /* set up pointer */
ct++;
}
inputBuffer[i] = '\0'; /* add a null char; make a C string */
start = -1;
break;
case '\n': /* should be the final char examined */
if (start != -1){
args[ct] = &inputBuffer[start];
ct++;
}
inputBuffer[i] = '\0';
args[ct] = NULL; /* no more arguments to this command */
break;
default : /* some other character */
if (start == -1)
start = i;
if (inputBuffer[i] == '&'){
*background = 1;
inputBuffer[i-1] = '\0';
}
} /* end of switch */
} /* end of for */
args[ct] = NULL; /* just in case the input line was > 80 */
for (i = 0; i <= ct; i++)
printf("args %d = %s\n",i,args[i]);
} /* end of setup routine */
int main(void)
{
char inputBuffer[MAX_LINE]; /*buffer to hold command entered */
int background; /* equals 1 if a command is followed by '&' */
char *args[MAX_LINE/2 + 1]; /*command line arguments */
int should_run = 1; /* flag to determine when to exit program */
while (should_run) {
//background=0;
printf("Msh>");
fflush(stdout);
setup(inputBuffer, args, &background);
execvp(args[0], args);
}
return 0;
}