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Using execvp() and fork()

vasiqshair (51)
For the life of me, I can't get this program to run. I tried this first on MS Visual Studio only to realize there are no fork and execvp on Windows. Then using Putty, I connected to my school's linux server, but that was no help either. I am really new to linux/unix. Input from you guys would be much appreciated.

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#include <iostream>
#include <fstream>
#include <cctype>
#include <stdio.h>
#include <sys/types.h>
using namespace std;

void  parse(char *line, char **argv)
{
     while (*line != '\0') {       /* if not the end of line ....... */ 
          while (*line == ' ' || *line == '\t' || *line == '\n')
               *line++ = '\0';     /* replace white spaces with 0    */
          *argv++ = line;          /* save the argument position     */
          while (*line != '\0' && *line != ' ' && 
                 *line != '\t' && *line != '\n') 
               line++;             /* skip the argument until ...    */
     }
     *argv = '\0';                 /* mark the end of argument list  */
}

void  execute(char **argv)
{
     pid_t  pid;
     int    status;
     
     if ((pid = fork()) < 0) {     /* fork a child process           */
          cout << "*** ERROR: forking child process failed\n" << endl;
          exit(1);
     }
     else if (pid == 0) {          /* for the child process:         */
          if (execvp(*argv, argv) < 0) {     /* execute the command  */
               cout << "*** ERROR: exec failed\n" << endl;
               exit(1);
          }
     }
     else {                                  /* for the parent:      */
          while (wait(&status) != pid)       /* wait for completion  */
               ;
     }
}
     
void  main()
{
     char  line[1024];             /* the input line                 */
     char  *argv[64];              /* the command line argument      */
     
     while (1) {                   /* repeat until done ....         */
          cout << "tish -> " << endl;     /*   display a prompt             */
          cin.get(line);              /*   read in the command line     */
          cout << endl;
          parse(line, argv);       /*   parse the line               */
          if (strcmp(argv[0], "exit") == 0)  /* is it an "exit"?     */
               exit(0);            /*   exit if it is                */
          execute(argv);           /* otherwise, execute the command */
     }
}

Catfish (666)
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