Programming Forums > Application Development > C++

L7Sqr · Jun 15th, 2005, 7:36 PM

Here is what I am trying to do:
From a TMemo object I am pulling a line out (full path name) and chopping the string to the file name (a batch file). No problem.
From there I want to execute the batch file by means of a system () command. Each time I try this, I get a dos window open/shut and the system command returns an error (non-zero).
errno is supposed to be set accordingly, but when I check it, I get an invalid value. Valid values include: ENOENT, ENOEXEC, ENOMEM, none of which I get. When I check, the errno is set to "Error 0", which to me means, no error....
However, system returns non-zero when passed a NULL pointer (indicating that a command processor IS available) and returns 1 (which is not indicated as a possible return value) when I pass a valid command.
Anyone have a sugestion on where I might be going wrong?
I have tried copying the file to the cwd to avoid PATH issues, but to no avail.

So you can avoid the obvious:
- yes, it is a valid batch file (it runs when invoked seperately)
- yes, I parsed the string properly - its the first thing I checked.
- I have tried both the full path and just the file name - same results.

My windows experience is limited, so please bear with me.
Thanks in advance for the help.

the code snippet, in case it helps you...

(Toggle Plain Text)

while (frmMain->memList->Lines->Count != 0) {
   batch = frmMain->memList->Lines->Strings[0];
   pos = batch.LastDelimiter("\\") + 1;
   len = batch.Length () - pos;
   sub = batch.SubString (pos, len + 1);
   error = system (batch.c_str ());
   if (error) {
      if (errno == ENOENT) {
         msg = "Path not found";
      } else if (errno == ENOEXEC) {
         msg = "Exec format error";
      } else if (errno == ENOMEM) {
         msg = "No memory";
      } else {
         msg = "Unknown error: " + IntToStr(error);
      }
      MessageBoxA (frmMain->Handle, msg.c_str(), "Error msg", 0);
      frmMain->btnAddFile->Enabled = false;
      return;
   }
   /*
    * ...
    */
}

Jun 15th, 2005, 7:36 PM	#1
L7Sqr Hobbyist Programmer Join Date: Jun 2005 Location: here Posts: 137 Rep Power: 0	system () command in Borland C++ Bldr. 4 Here is what I am trying to do: From a TMemo object I am pulling a line out (full path name) and chopping the string to the file name (a batch file). No problem. From there I want to execute the batch file by means of a system () command. Each time I try this, I get a dos window open/shut and the system command returns an error (non-zero). errno is supposed to be set accordingly, but when I check it, I get an invalid value. Valid values include: ENOENT, ENOEXEC, ENOMEM, none of which I get. When I check, the errno is set to "Error 0", which to me means, no error.... However, system returns non-zero when passed a NULL pointer (indicating that a command processor IS available) and returns 1 (which is not indicated as a possible return value) when I pass a valid command. Anyone have a sugestion on where I might be going wrong? I have tried copying the file to the cwd to avoid PATH issues, but to no avail. So you can avoid the obvious: - yes, it is a valid batch file (it runs when invoked seperately) - yes, I parsed the string properly - its the first thing I checked. - I have tried both the full path and just the file name - same results. My windows experience is limited, so please bear with me. Thanks in advance for the help. the code snippet, in case it helps you... (Toggle Plain Text) while (frmMain->memList->Lines->Count != 0) { batch = frmMain->memList->Lines->Strings[0]; pos = batch.LastDelimiter("\\") + 1; len = batch.Length () - pos; sub = batch.SubString (pos, len + 1); error = system (batch.c_str ()); if (error) { if (errno == ENOENT) { msg = "Path not found"; } else if (errno == ENOEXEC) { msg = "Exec format error"; } else if (errno == ENOMEM) { msg = "No memory"; } else { msg = "Unknown error: " + IntToStr(error); } MessageBoxA (frmMain->Handle, msg.c_str(), "Error msg", 0); frmMain->btnAddFile->Enabled = false; return; } /* * ... / } while (frmMain->memList->Lines->Count != 0) { batch = frmMain->memList->Lines->Strings[0]; pos = batch.LastDelimiter("\\") + 1; len = batch.Length () - pos; sub = batch.SubString (pos, len + 1); error = system (batch.c_str ()); if (error) { if (errno == ENOENT) { msg = "Path not found"; } else if (errno == ENOEXEC) { msg = "Exec format error"; } else if (errno == ENOMEM) { msg = "No memory"; } else { msg = "Unknown error: " + IntToStr(error); } MessageBoxA (frmMain->Handle, msg.c_str(), "Error msg", 0); frmMain->btnAddFile->Enabled = false; return; } / * ... */ }

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Programming Forums > Application Development > C++

system () command in Borland C++ Bldr. 4