这不起作用，注释不包含IP_ADDRstring
SSH_UN='user' IP_ADDR='192.168.1.101' cat <<"EOF" >> .ssh/config # VirtualBox (VB) on user's laptop at $IP_ADDR Host laptopvb Hostname $IP_ADDR User $SSH_UN ForwardAgent yes EOF 删除EOF周围的双引号：
IP_ADDR='192.168.1.101' cat <<EOF >> .ssh/config # VirtualBox (VB) on hobs laptop at $IP_ADDR Host laptopvb # manually set as a static IP on the VB Hostname $IP_ADDR User $SSH_UN ForwardAgent yes EOF
根据bash手册 ：
The format of here-documents is: <<[-]word here-document delimiter No parameter expansion, command substitution, arithmetic expansion, or pathname expansion is performed on word. If any characters in word are quoted, the delimiter is the result of quote removal on word, and the lines in the here-document are not expanded. If word is unquoted, all lines of the here-document are subjected to parameter expansion, command substitution, and arithmetic expansion.