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How to write to stdin of another program (program A -> [stdin]program B)

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# 1  
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
# 2  
Old 04-30-2008
It's against the:

https://www.unix.com/unix-dummies-que...om-forums.html

to double posts questions, continue here:

https://www.unix.com/unix-dummies-que...#post302190772

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