`sort` can take a file name as an operand, but here it must receive the contents of names.txt on its standard input instead. Type the complete command line that runs `sort` with its standard input redirected from names.txt.
LPIC-1 Exam 101-500, objective 103. GNU and Unix commands easy
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Answer
Type the answer.
Accepted answers
sort < names.txtsort <names.txtsort 0< names.txtsort 0<names.txt
Case sensitive — Linux is, and grading LS as ls would teach a falsehood.
Why
< redirects descriptor 0, standard input, from the named file: the shell opens the file and hands the open descriptor to the command, which then reads a stream and never learns the file's name. 0< is the same operator with the descriptor spelled out, just as 1> is the long spelling of >. This is also why `wc -l < file` prints a bare count while `wc -l file` labels it with the name, and why `sort < names.txt` and `cat names.txt | sort` deliver the same data by different routes.
Where this comes from
- Cited
- manual page bash(1)
Practise this
Reading one question is not practice. The trainer will draw a short set from objective 103 and space the ones you get wrong.
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