# Iteration 19: Coproc (Coprocess)
# === Basic coproc ===
=== simple coproc
coproc cat
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(coproc "COPROC" (command (word "cat")))
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=== coproc with arguments
coproc cat -n
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(coproc "COPROC" (command (word "cat") (word "-n")))
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=== named coproc
coproc MYCOPROC cat
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(coproc "COPROC" (command (word "MYCOPROC") (word "cat")))
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=== named coproc with args
coproc READER cat -n file.txt
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(coproc "COPROC" (command (word "READER") (word "cat") (word "-n") (word "file.txt")))
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=== coproc with brace group
coproc { cat; }
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(coproc "COPROC" (brace-group (command (word "cat"))))
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=== coproc with subshell
coproc ( cat )
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(coproc "COPROC" (subshell (command (word "cat"))))
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=== named coproc with brace group
coproc WORKER { while read line; do echo "$line"; done; }
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(coproc "WORKER" (brace-group (while (command (word "read") (word "line")) (command (word "echo") (word "\"$line\"")))))
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=== coproc with while loop
coproc while read x; do echo $x; done
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(coproc "COPROC" (while (command (word "read") (word "x")) (command (word "echo") (word "$x"))))
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=== coproc with redirect
coproc cat > /dev/null
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(coproc "COPROC" (command (word "cat") (redirect ">" "/dev/null")))
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=== coproc with input redirect
coproc cat < input.txt
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(coproc "COPROC" (command (word "cat") (redirect "<" "input.txt")))
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=== named coproc with redirect
coproc PROC cat 2>&1
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(coproc "COPROC" (command (word "PROC") (word "cat") (redirect ">&" 1)))
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=== coproc in list
coproc cat; echo started
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(semi (coproc "COPROC" (command (word "cat"))) (command (word "echo") (word "started")))
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=== coproc with and list
coproc cat && echo started
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(and (coproc "COPROC" (command (word "cat"))) (command (word "echo") (word "started")))
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=== coproc in pipeline is error but parses
echo foo | coproc cat
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(pipe (command (word "echo") (word "foo")) (coproc "COPROC" (command (word "cat"))))
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=== coproc with pipeline command
coproc cat | grep foo
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(pipe (coproc "COPROC" (command (word "cat"))) (command (word "grep") (word "foo")))
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=== lowercase coproc name
coproc myproc cat
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(coproc "COPROC" (command (word "myproc") (word "cat")))
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=== underscore in coproc name
coproc my_proc cat
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(coproc "COPROC" (command (word "my_proc") (word "cat")))
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=== coproc name with numbers
coproc proc1 cat
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(coproc "COPROC" (command (word "proc1") (word "cat")))
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=== coproc if compound
coproc if true; then cat; fi
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(coproc "COPROC" (if (command (word "true")) (command (word "cat"))))
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=== named coproc if compound
coproc MYIF if true; then cat; fi
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(coproc "MYIF" (if (command (word "true")) (command (word "cat"))))
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=== coproc for loop
coproc for x in a b; do echo $x; done
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(coproc "COPROC" (for (word "x") (in (word "a") (word "b")) (command (word "echo") (word "$x"))))
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=== coproc case statement
coproc case $x in a) cat;; esac
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(coproc "COPROC" (case (word "$x") (pattern ((word "a")) (command (word "cat")))))
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=== coproc with here doc
coproc cat <<EOF
hello
EOF
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(coproc "COPROC" (command (word "cat") (redirect "<<" "hello
")))
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=== coproc backgrounded (unusual but valid syntax)
coproc cat &
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(background (coproc "COPROC" (command (word "cat"))))
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=== coproc in subshell
(coproc cat)
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(subshell (coproc "COPROC" (command (word "cat"))))
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=== coproc arithmetic command
coproc (( x++ ))
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(coproc "COPROC" (arith (word " x++ ")))
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=== named coproc with process sub
coproc READER cat <(echo hello)
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(coproc "COPROC" (command (word "READER") (word "cat") (word "<(echo hello)")))
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