:) froger
ELF32X86_64 Frog Version 1.0d

"job" fload
"/bin/sh <${IPC0} >${IPC1} &" /SYS \ run DASH in background
CO:OPEN \ open IPC handles
: (LTYPE) CO:SRC 2@ CR TYPE ; \ word to print IPC data
' (LTYPE) is CO:READL \ assign word to data reader

"env" CO:PROTO \ command DASH to dump environment
CO:READL \ get and display the results
ENV=/home/sdwjack69/etc/minrc
PWD=/home/sdwjack69/fth/frog
HOME=/home/sdwjack69
IPC1=/home/sdwjack69/var/fifo/p1
IPC0=/home/sdwjack69/var/fifo/p0
SHLVL=1
BASH_ENV=/home/sdwjack69/etc/minrc
PATH=/home/sdwjack69/bin:/usr/local/bin:/usr/bin:/bin
BASH_FUNC_ipc%%=() { echo "STX" > ${IPC1};
eval "${@}" > ${IPC1};
echo "ETX" > ${IPC1}
} _=/usr/bin/env

'FOO="old magic XYZZY"' CO:WRITEL \ variable assignment in DASH
'echo "${FOO##*\ }"' CO:PROTO \ parse the variable in DASH
CO:READL \ get and display the results
XYZZY

:)
Note:
i. dash shell used instead of bash because it's leaner
i. a minimal environment was used with dash
i. CO:WRITEL write line to co-program
i. CO:PROTO write line to co-program; return data wrapped in STX...ETX
i. CO:READL read lines of data from co-program
--
me

Some refinements and notes:

i. Use bash for co-shell because it has more functions.
Use the leaner dash for forked-shell which loads every time used.
Minimal shell environment is used with both.

i. The co-shell which runs in background is prohibited from accessing
the keyboard. To do an operation like reading tty will need to be
done with the forked-shell. Data from the forked-shell can return
by the same pipe used by the co-shell output.

--
me