Update cheatsheets

tldr/coproc

@@ -28,6 +28,10 @@ source: https://github.com/tldr-pages/tldr.git
 
 `coproc {{name}} { while read line; do {{command1; command2; ...}}; done }`
 
+- Create a coprocess which repeatedly reads `stdin`, runs a pipeline on the input, and writes the output to `stdout`:
+
+`coproc {{name}} { while read line; do echo "$line" | {{command1 | command2 | ...}} | cat /dev/fd/0; done }`
+
 - Create and use a coprocess running `bc`:
 
 `coproc BC { bc --mathlib; }; echo "1/3" >&"${BC[1]}"; read output <&"${BC[0]}"; echo "$output"`