On 22/11/2023 19:17, Greg Wooledge wrote:
On Wed, Nov 22, 2023 at 07:06:58PM +0700, Max Nikulin wrote:
ssh localhost echo remote
echo local
This is like <https://mywiki.wooledge.org/BashFAQ/089>. ssh grabs
all of the stdin (until EOF) and leaves none for bash.
Thanks. I expected to find it among pitfalls.
I don't know dash's internals. Maybe dash reads an entire buffer's
worth of stdin at a time, instead of a command at a time as bash does.
It seems dash reads a block from stdin (and does not lseek back even for
regular files) only for commands. I do not see significant difference
when commands reading stdin are placed into a script
cmd='seq 1000000 | while read -r var ; do
printf "%s\n" "$var" ;
ssh localhost echo remote ;
done'
bash -c "$cmd"
dash -c "$cmd"
If the script is passed as an argument, not to stdin, then output contains
"local" in both cases.
Yes. In that case, bash is not competing with ssh for stdin.
I have found an attempt to report it:
https://lore.kernel.org/dash/6640a8ee-eda0-1e35-df1a-c8b303440...@mail.de/
stdin should be consumed line by line. Fri, 22 Oct 2021 13:11:43 +0200
No response.
