这里是问题： pc A ssh-> pc B：成功！ pc B ssh-> pc A：成功！
pcA>scp -P $port $files $pcB@$domain:"$path" #success
files 100% 154 17.6KB/s 00:00
但是！
pcB>scp -vvv -P $port $files $pcA@$domain:"$path" #failed with error code
Executing: program ssh.exe host $domain, user $pcA, command scp -v -t $path
CreateProcessW failed error:2
posix_spawn: No such file or directory