• Robert Fraser <fraserofthenight gmail.com> Dec 04 2007
• Bill Baxter <dnewsgroup billbaxter.com> Dec 04 2007
• Robert Fraser <fraserofthenight gmail.com> Dec 04 2007
• Nathan Reed <nathaniel.reed gmail.com> Dec 04 2007
• "Kris" <foo bar.com> Dec 04 2007

Robert Fraser <fraserofthenight gmail.com> writes:

I'd like at a particular point in my program to temporarily ignore all 
stdout (i.e. not have it written to the stream)... is there a way to do 
this? I want my program to work under both Phobos & Tango, so a way for 
both libraries would be great.

Thanks,
Robert

Bill Baxter <dnewsgroup billbaxter.com> writes:

Robert Fraser wrote:
 I'd like at a particular point in my program to temporarily ignore all 
 stdout (i.e. not have it written to the stream)... is there a way to do 
 this? I want my program to work under both Phobos & Tango, so a way for 
 both libraries would be great.
 


Phobos just uses the underlying C stream objects in the end, so you can 
use freopen on those.  Note that std.cstream functions will throw 
exceptions if the standard output streams are not open, so the code 
below freopens them to point to /dev/null or Nul.

Don't know if there's a better way, but this way has been working for me.

version(Tango) {
     ??
}
else {
     static this() {
         // redefine dout,derr,dlog to prevent IO exceptions
         version(Windows) {
             std.c.stdio.freopen("Nul", "w", dout.file);
             std.c.stdio.freopen("Nul", "w", derr.file);
         }
         else {
             std.c.stdio.freopen("/dev/null", "w", dout.file);
             std.c.stdio.freopen("/dev/null", "w", derr.file);
         }
     }
}

Robert Fraser <fraserofthenight gmail.com> writes:

Bill Baxter wrote:
 Robert Fraser wrote:
 I'd like at a particular point in my program to temporarily ignore all 
 stdout (i.e. not have it written to the stream)... is there a way to 
 do this? I want my program to work under both Phobos & Tango, so a way 
 for both libraries would be great.


 Phobos just uses the underlying C stream objects in the end, so you can 
 use freopen on those.  Note that std.cstream functions will throw 
 exceptions if the standard output streams are not open, so the code 
 below freopens them to point to /dev/null or Nul.
 
 Don't know if there's a better way, but this way has been working for me.
 
 version(Tango) {
     ??
 }
 else {
     static this() {
         // redefine dout,derr,dlog to prevent IO exceptions
         version(Windows) {
             std.c.stdio.freopen("Nul", "w", dout.file);
             std.c.stdio.freopen("Nul", "w", derr.file);
         }
         else {
             std.c.stdio.freopen("/dev/null", "w", dout.file);
             std.c.stdio.freopen("/dev/null", "w", derr.file);
         }
     }
 }


Thanks; that's what I needed! But how do I capture the current 
stdout/stderr so I can get them back (I've never done these scary stream 
thing before, obviously).

Nathan Reed <nathaniel.reed gmail.com> writes:

Robert Fraser wrote:
 Bill Baxter wrote:
 Robert Fraser wrote:
 I'd like at a particular point in my program to temporarily ignore 
 all stdout (i.e. not have it written to the stream)... is there a way 
 to do this? I want my program to work under both Phobos & Tango, so a 
 way for both libraries would be great.


 Phobos just uses the underlying C stream objects in the end, so you 
 can use freopen on those.  Note that std.cstream functions will throw 
 exceptions if the standard output streams are not open, so the code 
 below freopens them to point to /dev/null or Nul.

 Don't know if there's a better way, but this way has been working for me.

 version(Tango) {
     ??
 }
 else {
     static this() {
         // redefine dout,derr,dlog to prevent IO exceptions
         version(Windows) {
             std.c.stdio.freopen("Nul", "w", dout.file);
             std.c.stdio.freopen("Nul", "w", derr.file);
         }
         else {
             std.c.stdio.freopen("/dev/null", "w", dout.file);
             std.c.stdio.freopen("/dev/null", "w", derr.file);
         }
     }
 }


 Thanks; that's what I needed! But how do I capture the current 
 stdout/stderr so I can get them back (I've never done these scary stream 
 thing before, obviously).


I think you can just save the old values of dout.file and derr.file, and 
restore them later on (remembering to close the 'reopened' streams when 
you do so).

Thanks,
Nathan Reed

"Kris" <foo bar.com> writes:

With Tango you set either Stdout.stream() or Cout.output() to an output 
stream, which can be a file, socket, chunk of memory, or whatever. For 
example, to place all stdout and cout content into a file:

#   Cout.output (new FileOutput("redirected"));



"Robert Fraser" <fraserofthenight gmail.com> wrote in message 
news:fj4stk$2c1t$1 digitalmars.com...
 I'd like at a particular point in my program to temporarily ignore all 
 stdout (i.e. not have it written to the stream)... is there a way to do 
 this? I want my program to work under both Phobos & Tango, so a way for 
 both libraries would be great.

 Thanks,
 Robert