31 lines
1.2 KiB
Awk
Executable File
31 lines
1.2 KiB
Awk
Executable File
#!/usr/bin/awk -f
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# https://www.grymoire.com/Unix/Awk.html
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# awk (named for its creators aho, weinberger and kernighan) takes a a text
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# file as input. the awk program then processes that file line by line.
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# think of the awk program as performing some process for each line in the file.
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# or, think of an awk program as a big loop in which you define how to process
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# lines of input, one line per loop iteration.
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# the simplest awk program has the following structure:
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# PATTERN { ACTION }
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# ...where PATTERN is a text pattern that is to be matched in each successive
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# line of input, and ACTION is the code to execute if the match is successful.
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# the simplest possible PATTERN to match is nothing. it matches everything.
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# the following valid awk script will print each line that it matches, meaning
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# that it will print everything. whatever file you pipe into it will be printed
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# back, line by line.
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{ print }
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# an easy way to test this script is as follows (minus the greater-than sign):
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# > ./01.awk /etc/passwd
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# NOTE: see the shbang line? notice the "-f" after the awk filepath? that needs
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# to be there if you're piping a text file into an awk script. by contrast, see
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# script 00.awk which does not take a file as input and does not need the -f
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