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Lecture 2 — more shell, streams, and poetry quest
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Announcements
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hw0 due tonight
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for hw0, cd Desktop only makes sense on a Linux VM
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office hours on webpage
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I/O streams
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every process has 3 standard streams
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input (stdin), file descriptor 0
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the keyboard by default
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output (stdout), file descriptor 1
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the screen by default
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error (stderr), file descriptor 2
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the screen by default
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redirect to files
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>, >>, 2>, 2>>, &>
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> — save output
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>> — generate a file line by line (e.g., as part of a loop)
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2>, 2>>, &> — save errors, other info output to stderr (like time)
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redirect from files
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<, <<<
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redirect to other streams
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2>&1
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command > 2>&1 file vs command 2>&1 > file
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redirect to other commands
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pipe: |
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ls /usr/bin | less
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du | sort -nr
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shell
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general form: command [options] [args]
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alias
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alias rm=rm -i
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.bashrc
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history search
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ctrl-r, grep ~/.bash_history
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*.png -> all png files
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[abc]* -> all files whose names start with a, b, or c
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ls -l
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poetry quest
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wget http://courses.cs.washington.edu/courses/cse374/16wi/poetry_quest.tar
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tar -xf poetry_quest.tar
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readme file has instructions
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