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Full Discussion: C, UNIX: How to redirect 'stdout' to a file from a C code?
Top Forums Programming C, UNIX: How to redirect 'stdout' to a file from a C code? Post 302983598 by alex_5161 on Thursday 13th of October 2016 04:19:09 PM
Old 10-13-2016
Thank you, jim mcnamara, it is perfectly helps!
Sure here is more than I need in my case, but everything is clear and strait forward!
Additionaly, your code keep a way to switch back that not needed right now, but could be a task later on such approach!

Also I've found useful (by another reply) the 'freopen()' C-function and did it in very simple way, too.
(... for anybody else with the same task and for myself later, here is how I did it with freopen() ) :
Code:
#include <iostream>
#include <fstream>
#include <stdio.h>

using namespace std;

void redir(char* fl_nm)
{
  freopen(fl_nm,"a",stdout);
}

int main()
{
   cout << "starting - by cout\n";
   printf(" this written by printf()\n Following messages shoul go to the file '/tmp/tst_redir.log'\n");

   redir((char*)"/tmp/tst_redir.log");

   cout << ".. By 'cout' after using the redir(): this should be written to the file\n";
   printf(" .. By printf() after 'redir()'...\n");

  return 0;
}

But, again, thanks for your solution!!
 

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LEARN ABOUT DEBIAN

grc

GRC(1)							      General Commands Manual							    GRC(1)

NAME

       grc - frontend for generic colouriser grcat(1)

SYNOPSIS

       grc [options] command [args]

DESCRIPTION

       grc  will  execute  command  command  with optional parameters [args] piping its stdout or stderr into grcat, with apropriate configuration
       file.

       Configuration file for grc is determined by /etc/grc.conf file.

       Format of /etc/grc.conf: each entry consists of 2 lines, between entries there can be any number of empty lines or lines beginning  with  #
       (comments)

       First line is regular expression, second line the name of configuration file for grcat.

       Configuration file after the first regular expression matching command [args] will be passed to grcat as its configuration file

OPTIONS

       --help Show summary of options.

       --version
	      Display version.

       -e --stderr
	      Redirect error output. Unless -s is selected as well, this cancels redirection of standard output via grcat

       -s --stdout
	      Redirect standard output. Used to redirect standard output together with --stderr option.

       --colour=x
	      x is one of on off auto

	      --colour=on will colourise (default)

	      --colour=off will just execute command without colourising.

	      --colour=auto will test if standard output is a tty, and colourise only when it is.

SEE ALSO

       grcat(1)

AUTHOR

       Written by Radovan Garabik <garabik @ kassiopeia.juls.savba.sk>

																	    GRC(1)
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