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D - [Help] - Determining if a file or directory exists

reply "Andrew Edwards" <edwardsac spamfreeusa.com> writes:
The following program does not work because there is no exist() defined. How
would I go about defining such a function or can this be included in
std.file? Thanks for your assistance.

Andrew

==================

import std.stream;

void main ()
{
  char[] dirname = "pubs";
  char[] filename = "monitor.bat";

  chdir("c:\\");
  if(exist(dirname) && exist(dirname~"\\"~filename)) //can we have this in
file.d?
  {
    stdout.writeString("The pubs directory exists and ");
    stdout.writeLine("monitor.dat exists in the pubs directory.");
  }
  else
  {
    mkdir(dirname);
    chdir(dirname);
    write(filename, "ViewSonic GS790");
  }
}
Dec 14 2003
parent reply "Lars Ivar Igesund" <larsivar igesund.net> writes:
With the current functions in std, I think it is easiest to
implement exist by trying to read the file and catch the
exception.

bool exist(char [] file)
{
  bool result = true;
  try {
    read(file);
  }
  catch (FileException e) {
    result = false;
  }
  return result;
}

Lars Ivar Igesund

"Andrew Edwards" <edwardsac spamfreeusa.com> wrote in message
news:bri5v9$2l06$1 digitaldaemon.com...

 The following program does not work because there is no exist() defined.


How

 would I go about defining such a function or can this be included in
 std.file? Thanks for your assistance.

 Andrew

 ==================

 import std.stream;

 void main ()
 {
   char[] dirname = "pubs";
   char[] filename = "monitor.bat";

   chdir("c:\\");
   if(exist(dirname) && exist(dirname~"\\"~filename)) //can we have this in
 file.d?
   {
     stdout.writeString("The pubs directory exists and ");
     stdout.writeLine("monitor.dat exists in the pubs directory.");
   }
   else
   {
     mkdir(dirname);
     chdir(dirname);
     write(filename, "ViewSonic GS790");
   }
 }
Dec 14 2003
parent reply "Charles" <sanders-consulting comcast.net> writes:
Don't mean to sound snotty, but seeing MW's report on D's speed of exception
handling, I think a better alternative would be to use stat on linux, and
GetFileAttributes on Windows.

Pseudo code for windows, I'm actually installing a Linux box now so I'll try
to work this out on Linux as well:

alias std.toStrinz c_str;
bit fileExists(char [] name ) { return (GetFileAttributes( c_str(name) ) !=
0xFFFFFFFF); }

This actually compiles and works as expected ( it also works for
directories )

C



"Lars Ivar Igesund" <larsivar igesund.net> wrote in message
news:bri9o6$2qj7$1 digitaldaemon.com...

 With the current functions in std, I think it is easiest to
 implement exist by trying to read the file and catch the
 exception.

 bool exist(char [] file)
 {
   bool result = true;
   try {
     read(file);
   }
   catch (FileException e) {
     result = false;
   }
   return result;
 }

 Lars Ivar Igesund

 "Andrew Edwards" <edwardsac spamfreeusa.com> wrote in message
 news:bri5v9$2l06$1 digitaldaemon.com...

 The following program does not work because there is no exist() defined.


 How

 would I go about defining such a function or can this be included in
 std.file? Thanks for your assistance.

 Andrew

 ==================

 import std.stream;

 void main ()
 {
   char[] dirname = "pubs";
   char[] filename = "monitor.bat";

   chdir("c:\\");
   if(exist(dirname) && exist(dirname~"\\"~filename)) //can we have this




in

 file.d?
   {
     stdout.writeString("The pubs directory exists and ");
     stdout.writeLine("monitor.dat exists in the pubs directory.");
   }
   else
   {
     mkdir(dirname);
     chdir(dirname);
     write(filename, "ViewSonic GS790");
   }
 }
Dec 14 2003
next sibling parent reply "Andrew Edwards" <edwardsac spamfreeusa.com> writes:
First of all, thanks to both of you for your suggestions.

"Charles" wrote ...

 Don't mean to sound snotty, but seeing MW's report on D's speed of


exception

 handling, I think a better alternative would be to use stat on linux, and
 GetFileAttributes on Windows.


Where is GetFileAttributes defined? I assume it's defined in Kernel32.dll
but am unable to compile the program as the compiler keeps barking about
undefined identifier GetFileAttributes.
Dec 14 2003
parent reply "Andrew Edwards" <edwardsac spamfreeusa.com> writes:
 Where is GetFileAttributes defined? I assume it's defined in Kernel32.dll
 but am unable to compile the program as the compiler keeps barking about
 undefined identifier GetFileAttributes.


Never mind. I've located it in std.c.windows.windows. Thanks a million.

Andrew
Dec 14 2003
parent "Charles" <sanders-consulting comcast.net> writes:
No problemo,

also YT's win32 wrappers are great, i havent ever use phobos windows.
http://hp.vector.co.jp/authors/VA028375/contents/D_windows.h.html

C !

"Andrew Edwards" <edwardsac spamfreeusa.com> wrote in message
news:brii04$4m4$1 digitaldaemon.com...

 Where is GetFileAttributes defined? I assume it's defined in




Kernel32.dll

 but am unable to compile the program as the compiler keeps barking about
 undefined identifier GetFileAttributes.


 Never mind. I've located it in std.c.windows.windows. Thanks a million.

 Andrew
Dec 14 2003
prev sibling parent "Sean L. Palmer" <palmer.sean verizon.net> writes:
AFAIK this is the fastest way to check if a file exists on Windows.  Good
call Charles!

Sean

"Charles" <sanders-consulting comcast.net> wrote in message
news:brichi$2ug8$1 digitaldaemon.com...

 Don't mean to sound snotty, but seeing MW's report on D's speed of


exception

 handling, I think a better alternative would be to use stat on linux, and
 GetFileAttributes on Windows.

 Pseudo code for windows, I'm actually installing a Linux box now so I'll


try

 to work this out on Linux as well:

 alias std.toStrinz c_str;
 bit fileExists(char [] name ) { return (GetFileAttributes( c_str(name) )


!=

 0xFFFFFFFF); }

 This actually compiles and works as expected ( it also works for
 directories )

 C
Dec 15 2003