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# 1  
Old 06-13-2002
shell interpretation

I executed the following command in the korn shell:
$ variable1="qwerty" ls | sort
and the shell executed the 'ls | sort' command.

I would have expected an error message from the shell, but instead of that the shell ran the 'ls | sort' command and didn't realize the variable assignement.

I would really appreciate if someone could explain to me how the shell interprets this command line.

Thanks for helping.
# 2  
Old 06-13-2002
The shell spawns a subshell to run the command. The subshell creates an environment variable called variable1 and gives it the value qwerty. Then it runs the ls | sort pipeline. If instead of "ls |sort" you had run "env" or "printenv" you would have seen the new variable. But the original shell's environment remains untouched.
 

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