Bash: exec

 

 

 

1. -a name 替换command程序名 作为第0个参数
   

    

    

    

    

2. -c Execute COMMAND with an empty environment
   

    

    

    

    

3. -l  Place a dash in the zeroth argument to COMMAND
   

    

    

Execute command, replacing this shell with the specified program. arguments become the arguments to command, if command is not specified, any redirection take effect in the current shell

如果没有命令,存在redirections, exec会改变当前shell的redirections

 

 

If the command cannot be executed, a non-interactive shell exits, unless the shell option `execfail` is set

如果command不能执行,非交互式shell退出, interactive shell无影响

 

 

 

 

execfail 为 unset时, exec 直接退出

execfail 为 set时, 后面的继续执行

exec正常执行的情况, 后面的当然也不会继续执行