Thread: can c++ do batch file processing?

I have a directory, which contains 100,000 input text files. I need to read in each file, to do some computation.

The lousy way I thought of is create a name file which contains all the 100,000 input files name, i.e. each line contains the input file name. My program will use the name file and read in each line of the name file, put into a string, then use it to open the input text file. But this is tedious because I need to manually key in the input files names in the name file.

Ken, you are the man!!! Thanks alot! I go try it out

I tried this code below from FAQ > How do I... (Level 3) > Accessing a directory and all the files within it. But I encountered error when I'm using Microsoft Visual Studio 2005. Does any one knows the problem? It seems like .net does not support windows.h?

Code:

// xtree.cpp : Defines the entry point for the console application.
//
#include <stdio.h> 
#include <stdlib.h> 
#include <windows.h> 

void errormessage(void)
{
  LPVOID  lpMsgBuf;
  FormatMessage
  (
    FORMAT_MESSAGE_ALLOCATE_BUFFER | FORMAT_MESSAGE_FROM_SYSTEM | FORMAT_MESSAGE_IGNORE_INSERTS,
    NULL,
    GetLastError(),
    MAKELANGID(LANG_NEUTRAL, SUBLANG_DEFAULT),  // Default language
    (LPTSTR) & lpMsgBuf,
    0,
    NULL
  );
  fprintf(stderr, "%s\n", (char*)lpMsgBuf);
  LocalFree(lpMsgBuf);
}

void format_time(FILETIME *t, char *buff)
{
  FILETIME    localtime;
  SYSTEMTIME  sysloc_time;
  FileTimeToLocalFileTime(t, &localtime);
  FileTimeToSystemTime(&localtime, &sysloc_time);
  sprintf
  (
    buff,
    "%4d/%02d/%02d %02d:%02d:%02d",
    sysloc_time.wYear,
    sysloc_time.wMonth,
    sysloc_time.wDay,
    sysloc_time.wHour,
    sysloc_time.wMinute,
    sysloc_time.wSecond
  );
}

void format_attr(DWORD attr, char *buff)
{
  *buff++ = attr & FILE_ATTRIBUTE_ARCHIVE ? 'A' : '-';
  *buff++ = attr & FILE_ATTRIBUTE_SYSTEM ? 'S' : '-';
  *buff++ = attr & FILE_ATTRIBUTE_HIDDEN ? 'H' : '-';
  *buff++ = attr & FILE_ATTRIBUTE_READONLY ? 'R' : '-';
  *buff++ = attr & FILE_ATTRIBUTE_DIRECTORY ? 'D' : '-';
  *buff++ = attr & FILE_ATTRIBUTE_ENCRYPTED ? 'E' : '-';
  *buff++ = attr & FILE_ATTRIBUTE_COMPRESSED ? 'C' : '-';
  *buff = '\0';
}

struct flist
{
  int             num_entries;
  int             max_entries;
  WIN32_FIND_DATA *files;
};
void addfile(flist *list, WIN32_FIND_DATA data)
{
  if (list->num_entries == list->max_entries)
  {
    int             newsize = list->max_entries == 0 ? 16 : list->max_entries * 2;
    WIN32_FIND_DATA *temp = (WIN32_FIND_DATA *) realloc(list->files, newsize * sizeof(WIN32_FIND_DATA));
    if (temp == NULL)
    {
      fprintf(stderr, "Out of memory\n");
      exit(1);
    }
    else
    {
      list->max_entries = newsize;
      list->files = temp;
    }
  }

  list->files[list->num_entries++] = data;
}

int sortfiles(const void *a, const void *b)
{
  const WIN32_FIND_DATA *pa = (WIN32_FIND_DATA *) a;
  const WIN32_FIND_DATA *pb = (WIN32_FIND_DATA *) b;
  int                   a_is_dir = pa->dwFileAttributes & FILE_ATTRIBUTE_DIRECTORY;
  int                   b_is_dir = pb->dwFileAttributes & FILE_ATTRIBUTE_DIRECTORY;
  if (a_is_dir ^ b_is_dir)
  {
    // one of each, prefer the directories first
    if (a_is_dir) return(-1);
    if (b_is_dir) return(+1);
    return(0);
  }
  else
  {
    // both files, or both directories - return the strcmp result
    return(strcmp(pa->cFileName, pb->cFileName));
  }
}

void doit(char *root)
{
  flist           list = { 0, 0, NULL };
  HANDLE          h;
  WIN32_FIND_DATA info;
  int             i;

  // build a list of files
  h = FindFirstFile("*.*", &info);
  if (h != INVALID_HANDLE_VALUE)
  {
    do
    {
      if (!(strcmp(info.cFileName, ".") == 0 || strcmp(info.cFileName, "..") == 0))
      {
        addfile(&list, info);
      }
    } while (FindNextFile(h, &info));
    if (GetLastError() != ERROR_NO_MORE_FILES) errormessage();
    FindClose(h);
  }
  else
  {
    errormessage();
  }

  // sort them
  qsort(list.files, list.num_entries, sizeof(list.files[0]), sortfiles);

  // print out in sorted order
  int numdirs = 0;
  for (i = 0; i < list.num_entries; i++)
  {
    char  t1[50], t2[50], t3[50], a[10];
    format_time(&list.files[i].ftCreationTime, t1);
    format_time(&list.files[i].ftLastAccessTime, t2);
    format_time(&list.files[i].ftLastWriteTime, t3);
    format_attr(list.files[i].dwFileAttributes, a);
    if (list.files[i].dwFileAttributes & FILE_ATTRIBUTE_DIRECTORY)
    {
      // 'null' date for directory access times, which change each time
      // we run this tool
      sprintf(t2, "%4d/%02d/%02d %02d:%02d:%02d", 2000, 1, 1, 0, 0, 0);
    }

    printf("%s %10ld %s %s %s %s\\%s\n", a, list.files[i].nFileSizeLow, t1, t2, t3, root, list.files[i].cFileName);
    if (list.files[i].dwFileAttributes & FILE_ATTRIBUTE_DIRECTORY) numdirs++;
  }

  // now process all the sub-dirs
  // free all the files first, to save a bit of space
  // the sort function will have put them all at the end.
  list.files = (WIN32_FIND_DATA *) realloc(list.files, numdirs * sizeof(WIN32_FIND_DATA));
  for (i = 0; i < numdirs; i++)
  {
    char  newroot[MAX_PATH];
    sprintf(newroot, "%s\\%s", root, list.files[i].cFileName);
    SetCurrentDirectory(list.files[i].cFileName);
    doit(newroot);
    SetCurrentDirectory("..");
  }

  // free the remainder
  free(list.files);
}

void banner(void)
{
  //       12345678901234567890
  printf("Attribs ");
  printf("      Size ");
  printf("       CreationTime ");
  printf("     LastAccessTime ");
  printf("      LastWriteTime ");
  printf("Filename\n");
}

int main(int argc, char *argv[])
{
  if (argc > 1)
  {
    char  olddir[MAX_PATH];
    if (GetCurrentDirectory(MAX_PATH, olddir) == 0)
    {
      errormessage();
      exit(1);
    }

    if (!SetCurrentDirectory(argv[1]))
    {
      errormessage();
      exit(1);
    }

    banner();
    doit(".");
    SetCurrentDirectory(olddir);
  }
  else
  {
    banner();
    doit(".");
  }

  return(0);
}

If you are using MSVC++2005 you will need the platform SDK included for the compiler to read windows.h. That may be your problem. You can download it free from Microsoft's website

so I just download SDK from http://www.microsoft.com/downloads/d...displaylang=en

install it, then i'm able to use windows.h under msvc++2005?

thanks guys! i go try it out! big file size, got to wait for it to d/l =)

Originally Posted by Ken Fitlike

I supect the errors are unicode related; it will be simpler for that particular example to disable unicode. To do this: project menu -->'your_project' properties, configuration properties, set Character set to use multi-byte character set.

How do you know that? I only said I got errors and You have solved my problem! What is unicode and multi-byte? You are great, I salute you!