The `heredoc` program

heredoc runs a command with a certain string fed to a file descriptor.

Interface

     heredoc [ -d ] fd string prog...

heredoc execs into prog... with string available on the fd file descriptor.
string must not contain a null character.

-d : run the process feeding string to fd as a grandchild of heredoc. This is meant to prevent a zombie from hanging around if prog... has read string and fails to wait for its children.

heredoc is meant to be used in place of the shell << construct, which includes here-documents into scripts.