In a fresh installation of iSH, the special files stdin, stdout and stderr are missing under /dev. Running something like echo hello > /dev/stderr in the shell doesn't produce any output, instead it simply creates a regular file at /dev/stderr and writes the output into it.
As a workaround, manually running ln -s /proc/self/fd/0 /dev/stdin (and the same for 1/stdout and 2/stderr) seems to work.
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As a workaround, manually running
ln -s /proc/self/fd/0 /dev/stdin(and the same for1/stdoutand2/stderr) seems to work.