$ # Fail log while installing LibRTMP via brew on macOS HighSierra.
$ # ------------------------------------------------------------------
$ # TL;DR
$ #  2018/06/24 Still can NOT install them. Provably deprecated.
$ # ------------------------------------------------------------------
$ #  Env
$ # ------------------------------------------------------------------
$ sw_vers
ProductName:	Mac OS X
ProductVersion:	10.13.5
BuildVersion:	17F77
$ brew --version
Homebrew 1.6.9-17-gb87fc8c
Homebrew/homebrew-core (git revision 89b66f; last commit 2018-06-24)
$ # ------------------------------------------------------------------
$ #  Install log
$ # ------------------------------------------------------------------
$ # Install LibRTMP
$ brew install librtmp
Error: No available formula with the name "librtmp"
==> Searching for a previously deleted formula (in the last month)...
Warning: homebrew/core is shallow clone. To get complete history run:
  git -C "$(brew --repo homebrew/core)" fetch --unshallow

Error: No previously deleted formula found.
==> Searching for similarly named formulae...
Error: No similarly named formulae found.
==> Searching taps...
==> Searching taps on GitHub...
Error: No formulae found in taps.
$ # (fail) oh...
$
$ # Update brew
$ brew update
Already up-to-date.
$
$ # Inspect brew
$ brew doctor
Please note that these warnings are just used to help the Homebrew maintainers
with debugging if you file an issue. If everything you use Homebrew for is
working fine: please don't worry or file an issue; just ignore this. Thanks!

Warning: "config" scripts exist outside your system or Homebrew directories.
`./configure` scripts often look for *-config scripts to determine if
software packages are installed, and what additional flags to use when
compiling and linking.

Having additional scripts in your path can confuse software installed via
Homebrew if the config script overrides a system or Homebrew provided
script of the same name. We found the following "config" scripts:
  /Volumes/Macintosh_SD/Users/admin/.pyenv/shims/python-config
  /Volumes/Macintosh_SD/Users/admin/.pyenv/shims/python3-config
  /Volumes/Macintosh_SD/Users/admin/.pyenv/shims/python3.6-config
  /Volumes/Macintosh_SD/Users/admin/.pyenv/shims/python3.6m-config
$ # (not much problem) hmmm...
$
$ # Re-fetch repo unshallow as told
$ git -C "$(brew --repo homebrew/core)" fetch --unshallow
remote: Counting objects: 317485, done.
remote: Compressing objects: 100% (136091/136091), done.
remote: Total 317485 (delta 182135), reused 313936 (delta 178598), pack-reused 0
Receiving objects: 100% (317485/317485), 85.60 MiB | 2.46 MiB/s, done.
Resolving deltas: 100% (182135/182135), completed with 3538 local objects.
$
$ # Update brew
$ brew update
Already up-to-date.
$
$ # Install LibRTMP
$ brew install librtmp
Error: No available formula with the name "librtmp"
==> Searching for a previously deleted formula (in the last month)...
Warning: homebrew/core is shallow clone. To get complete history run:
  git -C "$(brew --repo homebrew/core)" fetch --unshallow

Error: No previously deleted formula found.
==> Searching for similarly named formulae...
Error: No similarly named formulae found.
==> Searching taps...
==> Searching taps on GitHub...
Error: No formulae found in taps.
$ # (fail) :-( OMG
$
$ # Reset repo unshallow
$ cd "$(brew --repo)" && git fetch --unshallow && git reset --hard origin/master && brew update
remote: Counting objects: 56322, done.
remote: Compressing objects: 100% (16169/16169), done.
remote: Total 56322 (delta 39913), reused 54816 (delta 38677), pack-reused 0
Receiving objects: 100% (56322/56322), 8.57 MiB | 1.81 MiB/s, done.
Resolving deltas: 100% (39913/39913), completed with 202 local objects.
HEAD is now at b87fc8c53 Merge pull request #4369 from MikeMcQuaid/cache_store_mkpath
Already up-to-date.
$
$ # Install LibRTMP
$ brew install librtmp
Error: No available formula with the name "librtmp"
==> Searching for a previously deleted formula (in the last month)...
Error: No previously deleted formula found.
==> Searching for similarly named formulae...
Error: No similarly named formulae found.
==> Searching taps...
==> Searching taps on GitHub...
Error: No formulae found in taps.
$ # (fail) ヽ(`Д´)ﾉ WTF!!