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Top Forums Programming How to write to stdin of another program (program A -> [stdin]program B) Post 302190791 by vvaidyan on Wednesday 30th of April 2008 01:34:55 PM
Old 04-30-2008
How to write to stdin of another program (program A -> [stdin]program B)

Hi,
Program A: uses pipe()

I am able to read the stdout of PROGAM B (stdout got through system() command) into PROGRAM A using:

* child
-> dup2(fd[1], STDOUT_FILENO);
-> execl("/path/PROGRAM B", "PROGRAM B", NULL);

* parent
-> char line[100];
-> read(fd[0], line, 100);


Question:
---------
How to write to stdin of PROGRAM B from PROGRAM A?
* should I use a different pipe?
* how to I read stdin in PROGRAM B? using cin?

Thanks in advance,
Vivek
 

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RARUN2(1)						    BSD General Commands Manual 						 RARUN2(1)

NAME
rarun2 -- radare2 utility to run programs in exotic environments SYNOPSIS
rarun2 [[script.rr2]] DESCRIPTION
This program is used as a launcher for running programs with different environment, arguments, permissions, directories and overridden default filedescriptors. The program just accepts a single argument which is the filename of the configuration file to run the program. It is useful when you have to run a program using long arguments or pass long data to stdin or things like that usually required for exploit- ing crackmes :) DIRECTIVES
The rr2 (rarun2) configuration file accepts the following directives, described as key=value entries and comments defined as lines starting with '#'. program path to program to be executed stdout select file to replace stdout file descriptor stdin select file to read data from stdin input set string to be passed to the program via stdin chdir change directory before executing the program chroot run the program in chroot. requires some previous setup preload preload a library (not supported on Windows, only linux,osx,bsd) setuid set process uid seteuid set effective process uid setgid set process group id setegid set effective process group id setenv set value for given environment variable arg[0-3] set value for argument N passed to the program EXAMPLE
$ cat foo.rr2 #!/usr/bin/rarun2 program=./pp400 arg0=10 stdin=foo.txt chdir=/tmp #chroot=. ./foo.rr2 SEE ALSO
radare2(1), rahash2(1), rafind2(1), rabin2(1), ranal2(1), radiff2(1), ragg2(1), rasm2(1), AUTHORS
pancake <pancake@nopcode.org> BSD
Oct 11, 2011 BSD
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