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pages.pl/common/awk.md

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+# awk
+
+> A versatile programming language for working on files.
+> More information: <https://github.com/onetrueawk/awk>.
+
+- Print the fifth column (a.k.a. field) in a space-separated file:
+
+`awk '{print $5}' {{filename}}`
+
+- Print the second column of the lines containing "something" in a space-separated file:
+
+`awk '/{{something}}/ {print $2}' {{filename}}`
+
+- Print the last column of each line in a file, using a comma (instead of space) as a field separator:
+
+`awk -F ',' '{print $NF}' {{filename}}`
+
+- Sum the values in the first column of a file and print the total:
+
+`awk '{s+=$1} END {print s}' {{filename}}`
+
+- Sum the values in the first column and pretty-print the values and then the total:
+
+`awk '{s+=$1; print $1} END {print "--------"; print s}' {{filename}}`
+
+- Print every third line starting from the first line:
+
+`awk 'NR%3==1' {{filename}}`
+
+- Print all values starting from the third column:
+
+`awk '{for (i=3; i <= NF; i++) printf $i""FS; print""}' {{filename}}`
+
+- Print different values based on conditions:
+
+`awk '{if ($1 == "foo") print "Exact match foo"; else if ($1 ~ "bar") print "Partial match bar"; else print "Baz"}' {{filename}}`