passing a pipe as an argument to sort -m

Question

I am wondering if it is possible to send multiple pipes lets say 3 as arguments to be merged with sort -m in c.

For example execvp("sort", "sort", "-m", pipe1_read_end, pipe2_read_end, NULL)

Answer 1

If this is only targeting Linux, you can pass strings of the form:

/dev/fd/<number>

...representing your pipes, where <number> is, of course, the FD table entry number for the file descriptor in question. In fact, bash does this itself if you run

sort -m <(something) <(something)

For a more OS-agnostic solution, one typically uses named FIFOs (and this is what bash does with the <() construct if it detects that it's on an operating system that doesn't provide /dev/fd/ ).