making shell for homework - c

Question

#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <sys/types.h>
#include <string.h>
#include <sys/stat.h>
#include <fcntl.h>
void exec(char **args){
pid_t pid;
int status;
if ((pid = fork()) < 0) {
printf("*** ERROR: forking child process failed\n");
exit(1);
}
else if (pid == 0) {
if(execvp(args[0],args)<0)//{
//printf("argv[0]=%s argv[1]=%s",args[0],args[1]);
printf("**error in exec\n");
}
else {
while (wait(&status) != pid);
}
}
void exec2(char **args, char *file){
printf("file =%s\n",file);
int fd;
pid_t pid;
int status;
if ((pid = fork()) < 0) {
printf("*** ERROR: forking child process failed\n");
exit(1);
}
else if (pid == 0) {
fd = open(file, O_RDWR | O_CREAT, (mode_t)0600);
close(1);
dup2(fd, 1);
if(execvp(args[0],args)<0){
printf("**error in exec");
}
else {
printf("\nhere\n");
close(fd);
while (wait(&status) != pid){
fflush(stdout) ;
}
}
}
close (fd);
}
void main(){
char *command;
char inp[512];
char *filepath;
size_t size=0;
char *substr;
char *args[512];
command = (char *) malloc(sizeof(char *) * 512);
int flag=0;
int redirect=0;
int i=0;
while (1){
printf("$ ");
command = fgets(inp, 512/*sizeof(char *)*/, stdin);
command[strlen(command)-1]='\0';
if (strchr(command,'>')){
redirect=1;
strtok_r(command,">",&filepath);
}
size_t siz=4;
//printf("command=%s\n",command);
int i=0;
while(1){
//printf("i=%d\n",i);
char *tok = strtok_r(command," ",&substr);
if (tok==NULL){
break;
}
args[i++] = tok;
/* printf("tok=%s\n",tok);
printf("len tok = %d\n",(int)strlen(tok));
printf("command=%s\n",command);
printf("substr=%s\n",substr);
*/ command = substr;
}
//printf("args[0]=%s",args[0]);
if (!strncasecmp(args[0],"exit",siz) || !strncasecmp(args[0],"quit",siz))
{
printf("\nBye\n");
exit(0);
}
else if(strcmp(args[0],"cd")==0){
chdir(args[1]);
//printf("chdir") ;
//system("pwd");
}
else if (redirect==1){
exec2(args,filepath);
}
else exec(args);
}
}
Okay this is my code for my shell. When i run it, i put ls and it gives correct output. Then i put ls -l and then ls again and it gives
ls: cannot access : No such file or directory
Also when i use cd, ls doesnt give output and pwd says "ignoring unused arguments"
ALso cat doesnt work.
Though mkdir, ps and ls -l works.

Answer 1

Don't close stdout!
Do it like this, after the fork and before the exec:
if (child) {
int fd = open(file, O_RDWR | O_CREAT, (mode_t)0600);
close(1);
dup2(fd, 1);
if(execvp(args[0],args)<0){
printf("**error in exec");
}
}