Sourcing a script from a pipe is not reliable

[Jeremy]

Configuration Information [Automatically generated, do not change]:

Machine: Mac

OS: Darwin

Compiler: gcc

Compilation CFLAGS: Xcode

uname output: Darwin Octo.local 15.6.0 Darwin Kernel Version 15.6.0: Thu
Jun 21\

 20:07:40 PDT 2018; root:xnu-3248.73.11~1/RELEASE_X86_64 x86_64

Machine Type: x86_64-Apple-Darwin


Bash Version: 3.2

Patch Level: 48

Release Status: relase


Description:

Sourcing a script from a pipe is not reliable.


Repeat-By:

This command line should run forever:


  i=0; while [ "_$(echo echo '$1' | . /dev/stdin yes)" = "_yes" ]; \

  do echo -n .; ((i++)); done; printf "\n%s\n" $i


When I run it, it usually terminates with $i much less than 1,000.