popen() works, but now?

[Ronald Bultje <rbultje ronald bitfreak net>]

Hi again,

I learned to use FILE *some_pipe = popen(command,"w"); to open a program
and write some data to it's stdin. The program receives the data I send to
it (press enter to continue -> fprintf(some_pipe, "\n");, for example), but
for some reason, this takes effect *after* I close my main application.
Should I make this a thread or something? It is supposed to receive and
process this data *while* the main application is running.

Ronald