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Given a pipe of the form C1 | C2, if C2 takes more than one positional argument, is it possible to choose where the output of C1 is going?
Consider the following example.
$ cat myscript
#!/bin/bash
cat $1
cat $2
$ cat world.txt
World
$ echo "Hello" | ./myscript world.txt
World
Hello
I want the final output to be in correct order (Hello World) by altering only the right side of the pipeline.
You might want to try this:
echo "Hello" | ./myscript /dev/stdin world.txt
So that standard input of ./myscript feeds into the first "cat"
C1output is not going into$2. Addecho <$2>to the script and you will see that. So the whole premise of your question is not correct.stdoutof one program to thestdinof the other. It has nothing to do with the script arguments. What you see happening is that$2is actually empty in your example so the lastcatreads fromstdinwhich then comes from the pipe.cat.cat(concatenate) will read all files mentioned in its argument lists and output them one after another. Same as what your script is trying to do, but for more and less than 2.