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What would be ideal to solve first is some sort of initial format negotiation on pipes. Otherwise you will end up with the wrong thing happening (eg having to reimplement every tool, spewing "rich" format to tools that don't know it, or regular text to tools that could do better).

We've already seen something like this - for example ls does column output if going directly to a screen, otherwise one per line, and many tools will output in colour if applicable. However this is enabled by isatty() which uses system calls, and inspecting the terminal environment for colour support.

Another example is telnet which does feature negotiations if the other end is a telnet daemon, otherwise just acts as a "dumb" network connection. (By default the server end initiates the negotiations.)

However the only way I can see this being possible with pipes is with kernel/syscall support. It would provide a way for either side to indicate support for richer formats, and let them know if that is mutually agreeable, otherwise default to compatible plain old text. For example an ioctl could list formats supported. A recipient would supply a list before the first read() call. The sender would then get that list and make a choice before the first write() call. (This is somewhat similar to how clipboards work.)

So the question becomes would we be happy with a new kernel call in order to support rich pipes, which automatically use current standard behaviour in its absence or when talking to non-rich enabled tools?

I would love it if grep/find/xargs automatically knew about null terminating.

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-Z, --null Output a zero byte (the ASCII NUL character) instead of the character that normally follows a file name. For example, grep -lZ outputs a zero byte after each file name instead of the usual newline. This option makes the output unambiguous, even in the presence of file names containing unusual characters like newlines. This option can be used with commands like find -print0, perl -0, sort -z, and xargs -0 to process arbitrary file names, even those that contain newline characters. -z, --null-data Treat the input as a set of lines, each terminated by a zero byte (the ASCII NUL character) instead of a newline. Like the -Z or --null option, this option can be used with commands like sort -z to process arbitrary file names.

--null -0 Input items are terminated by a null character instead of by whitespace, and the quotes and backslash are not special (every character is taken literally). Disables the end of file string, which is treated like any other argument. Useful when input items might contain white space, quote marks, or backslashes. The GNU find -print0 option produces input suitable for this mode.

-print0 True; print the full file name on the standard output, followed by a null character (instead of the newline character that -print uses). This allows file names that con‐ tain newlines or other types of white space to be correctly interpreted by programs that process the find output. This option corresponds to the -0 option of xargs.