Shell 脚本避免多次重复 source

 

 

https://kodango.com/avoid-repeated-source-in-shell

${!_sourced_}是间接引用，这个执行没问题，source 会报错 bad substitution 

_sourced_=__sourced_$$__  echo Flag variable $_sourced_=${!_sourced_}  if [ -z ${!_sourced_} ]; then     eval $_sourced_=1     echo It is the first time to source script else     echo The script have been sourced fi

 

改为下面就可以正常source

_sourced_=__sourced_$$__  sourced=`eval echo '$'$_sourced_`  echo Flag variable $_sourced_=${sourced}  if [ -z ${sourced} ]; then     eval $_sourced_=1     echo It is the first time to source script else     echo The script have been sourced fi

 

或者

_sourced_=__sourced_$$__  eval sourced=\$$_sourced_  echo Flag variable $_sourced_=${sourced}  if [ -z ${sourced} ]; then     eval $_sourced_=1     echo It is the first time to source script else     echo The script have been sourced fi  _sourced_=__sourced_$$__ echo $_sourced_