This is what I have"
#!/bin/bash
MAX=3
for((ctr = 0;ctr < MAX; ++ctr))
do
./make.o > out$ctr.txt
output$ctr.txt
done
so I want to take put the output of make.o into out$ctr.txt and in my make.o I call cin, could I take output$ctr.txt as input? I would rather not use input redirection since I would have to rewrite the program.
EDIT: I do not want to use < because then it will give me the contents of the file output$ctr.txt, I do want the actual name of the file not the contents
Do you mean like this
./make.o < output$ctr.txt > out$ctr.txt
Edit: if you want the name, then just do this:
./make.o output$ctr.txt > out$ctr.txt
or maybe this, to echo the name so it can be read from C++ cin:
echo output$ctr.txt | ./make.o > out$ctr.txt
But what you actually want is:
./make.o output$ctr.txt >out$ctr.txt
where output$ctr.txt is a command-line argument to your program.
Assuming a C++ program, since you mention cin, you handle command-line arguments like this:
int main(int argc, char *argv[])
{
if (argc < 2) {
// argv[0] usually contains the program name
std::cerr << "missing argument\n"
<< "Syntax: " << argv[0] << " input-file\n";
return -1;
}
char *input = argv[1]; // = "output$ctr.txt"
// ...
}
It sounds like you just want;
./make.o >out$ctr.txt <output$ctr.txt
> redirects the file descriptor STDOUT_FILENO which is associated with FILE *stdout and std::cout.
< redirects the file descriptor STDIN_FILENO which is associated with FILE *stdin and std::cin.
Just a comment about you loop, another more simpler way to write it is
#!/bin/bash
for i in {0..2}
do
echo $i
done
