emcc should read from stdin when no input files given

[smehrbrodt]

The following command works with clang:
echo "__clang_major__.__clang_minor__.__clang_patchlevel__" | clang -E -P -

If you try the same with emcc:
echo "__clang_major__.__clang_minor__.__clang_patchlevel__" | emcc -E -P -
you get an error: ERROR root: no input files

emcc should read from stdin when no input files are given.

[kripken]

#3552 also talks about this. But it has a mix of other things so let's keep this open too.

[smehrbrodt]

Is someone already working on this or could I go ahead and create a pull request?

[kripken]

No one that I know, feel free to work on it.

[smehrbrodt]

Might use something like https://docs.python.org/2/library/fileinput.html
Will see if I can get this working.

[davide-baldo]

can't you just use /dev/stdin as a workaround?

[pimlu]

/dev/stdin would work on Linux and OSX, but not on Windows, unfortunately.

[smehrbrodt]

can't you just use /dev/stdin as a workaround?

I tried to replace emcc -E -P - with emcc -E -P /dev/stdin. Unfortunately, this hit another bug (#3845)

[stale]

This issue has been automatically marked as stale because there has been no activity in the past 2 years. It will be closed automatically if no further activity occurs in the next 7 days. Feel free to re-open at any time if this issue is still relevant.