When an argument is given to cat, it should ignore stdin (unless one of the arguments was -, see #4). SUSv3 explicitly specifies this behavior:

The standard input shall be used only if no file operands are specified, or if a file operand is '-'.

The current behavior does the opposite and ignores the arguments:

$ echo hi | ./bin/cat ./index.js
hi

Thanks,
Kevin

It would be great if cat could support - as an argument to denote stdin as specified by SUSv3.

This would allow users to put a header/footer around stdin using cat as follows:

$ cat header - footer

Thanks,
Kevin

I'm guessing nextback isnt isomorphic and will need a PR.

I found it very unexpected that cat would buffer its entire input before writing anything to stdout. Although buffering behavior is unspecified in SUSv3 (other than -u disabling any buffering that may be present), I am not aware of any other cat implementations which buffer all input. GNU cat ignores -u and always operates unbuffered. Most of the other implementations I've seen use it to disable output buffering by the standard library. Is there a reason that cat buffers all of its input (possibly GB worth) before writing any?

Thanks,
Kevin

[Note: This is the first of several issues. I'm happy to send PRs for some/all of these, but most need some discussion first.]

When running cat with stdin redirected from a file yields the following result:

$ ./bin/cat < ./index.js 
/tmp/posix-cat/bin/cat:9
cat.on('end', process.stdin.end.bind(process.stdin))
                               ^

TypeError: Cannot read property 'bind' of undefined
    at Object.<anonymous> (/media/linuxdata/kevin/tmp/posix-cat/bin/cat:9:32)
    at Module._compile (module.js:409:26)
    at Object.Module._extensions..js (module.js:416:10)
    at Module.load (module.js:343:32)
    at Function.Module._load (module.js:300:12)
    at Function.Module.runMain (module.js:441:10)
    at startup (node.js:134:18)
    at node.js:962:3

This is because process.stdin is tty.ReadStream when stdin is a TTY and fs.ReadStream when it is a file.

Do you recall the reason for calling .end() here?

Thanks,
Kevin