• Charles (13/13) Oct 31 2005 Is there any way to capture stdout from an exec/system call into the pro...
• zwang (5/25) Oct 31 2005 As far as I know, you have to call platform-specific API to do this in
• Regan Heath (3/22) Oct 31 2005 Yep. Here are some examples, they may even work ;)
• Georg Wrede (14/37) Oct 31 2005 For debugging or quick-and-dirty purposes one might also do something

Charles <Charles_member pathlink.com> writes:

Is there any way to capture stdout from an exec/system call into the program ?

In perl I'd do this:

my  output = `ls`; 
print  output;

This above allows me to parse/manipulate the output of the ls command.

How would I do the equiv in D ? 
The following executes the ls command but doesn't give me the output inside the
program.
import std.process;
char * cmd = "/bin/ls"
system(cmd);

any hlp apprec,
Charles

zwang <nehzgnaw gmail.com> writes:

Charles wrote:
 Is there any way to capture stdout from an exec/system call into the program ?
 
 In perl I'd do this:
 
 my  output = `ls`; 
 print  output;
 
 This above allows me to parse/manipulate the output of the ls command.
 
 How would I do the equiv in D ? 
 The following executes the ls command but doesn't give me the output inside the
 program.
 import std.process;
 char * cmd = "/bin/ls"
 system(cmd);
 
 any hlp apprec,
 Charles
 
 

As far as I know, you have to call platform-specific API to do this in 
D. In Windows, related functions include CreatePipe, 
SetHandleInformation, CreateProcess, PeekNamedPipe, WaitForSingleObject, 
ReadFile, and CloseHandle.

"Regan Heath" <regan netwin.co.nz> writes:

On Mon, 31 Oct 2005 22:14:59 +0800, zwang <nehzgnaw gmail.com> wrote:
 Charles wrote:
 Is there any way to capture stdout from an exec/system call into the  
 program ?
  In perl I'd do this:
  my  output = `ls`; print  output;
  This above allows me to parse/manipulate the output of the ls command.
  How would I do the equiv in D ? The following executes the ls command  
 but doesn't give me the output inside the
 program.
 import std.process;
 char * cmd = "/bin/ls"
 system(cmd);
  any hlp apprec,
 Charles

 As far as I know, you have to call platform-specific API to do this in  
 D. In Windows, related functions include CreatePipe,  
 SetHandleInformation, CreateProcess, PeekNamedPipe, WaitForSingleObject,  
 ReadFile, and CloseHandle.

Yep. Here are some examples, they may even work ;)

Regan

Georg Wrede <georg.wrede nospam.org> writes:

Regan Heath wrote:
 On Mon, 31 Oct 2005 22:14:59 +0800, zwang <nehzgnaw gmail.com> wrote:
 
 Charles wrote:

 Is there any way to capture stdout from an exec/system call into the  
 program ?
  In perl I'd do this:
  my  output = `ls`; print  output;
  This above allows me to parse/manipulate the output of the ls command.
  How would I do the equiv in D ? The following executes the ls 
 command  but doesn't give me the output inside the
 program.
 import std.process;
 char * cmd = "/bin/ls"
 system(cmd);
  any hlp apprec,
 Charles



For debugging or quick-and-dirty purposes one might also do something 
like this:

system("ls -l /root /home >/tmp/lsout 2>/tmp/lserr ");

Whereafter you can the read the files into your program.
This has the advantage of separating error and standard output from each 
other. For example, on my machine the files end up containing:

lsout:
   /home:
   total 4
   drwxr-xr-x  24 georg georg 4096 Nov 1 00:34 georg

and lserr:
   ls: /root: Permission denied


 As far as I know, you have to call platform-specific API to do this 
 in  D. In Windows, related functions include CreatePipe,  
 SetHandleInformation, CreateProcess, PeekNamedPipe, 
 WaitForSingleObject,  ReadFile, and CloseHandle.

 
 Yep. Here are some examples, they may even work ;)

Cool!