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When i run the program with the ls > filename command it prints the results in the file but after that it doesn't respond to other commands like ls etc . Here is the code :

#include <stdio.h>
#include <unistd.h>
#include <stdlib.h>
#include <sys/wait.h>
#include <sys/types.h>
#include <string.h>
#include <fcntl.h>

void execute(char **argv, char ** k, int *l)
{
    pid_t pid;
    int file_descriptor;
    int status;

    int file;

    if ((pid = fork()) < 0)
    {
        printf("*** ERROR: forking child process failed\n");
        exit(1);
    }
    else if (pid == 0)
    {

        if (l = 1)
        {
            file = open(k, O_WRONLY | O_CREAT | O_TRUNC, S_IRUSR | S_IWUSR | S_IXUSR | S_IRGRP | S_IWGRP | S_IXGRP | S_IROTH | S_IWOTH | S_IXOTH);
            file_descriptor = dup2(file, 1);

        }

        if (execvp(argv[0], argv) < 0)
        {
            printf("*** ERROR: exec failed\n");
            exit(1);
        }

    }
    else
    {

        while (wait(&status) != pid)
            ;

    }
}

void main(void)
{
    char **name = (char**) malloc(256 * sizeof(char));
    char line[1024];
    char ** k;
    int file;
    int i;
    int *l;

    while (1)
    {
        l = 0;
        i = 0;
        printf("myShell3 -> ");
        gets(line);              // gets the input command from user
        printf("\n");
        name[i] = strtok(line, " ");

        while (name[i] != NULL)
        {
            if (strcmp(name[i], ">") == 0)
            {
                i++;

                l = 1;

                k = strtok(NULL, " ");
                name[i - 1] = name[i];

            }

            else if (!strcmp(name[i], "<"))
            {
                i++;
                name[i] = strtok(NULL, " ");
                name[i - 1] = name[i];
            }
            else
            {

                i++;

                name[i] = strtok(NULL, " ");
            }

        }

        execute(name, k, l);

    }

}

I have spent many hours on how to fix this but didnt find solution . Any help would be very much appreciated

LPs
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    [why-is-the-gets-function-so-dangerous-that-it-should-not-be-used](http://stackoverflow.com/questions/1694036/why-is-the-gets-function-so-dangerous-that-it-should-not-be-used) – LPs May 12 '17 at 14:09
  • 2
    Turn up compiler warnings (`gcc -Wall`). There are several compiler warnings you need to adress. – Klas Lindbäck May 12 '17 at 14:37
  • Usually `sizeof(char) != sizeof(*char)` (we don't consider 8-bit address buses here). – 0andriy May 12 '17 at 15:14

0 Answers0