notebook/notes/gawk/variables.md

title	TARGET DECK	FILE TAGS	tags
GAWK	Obsidian::STEM	linux::cli gawk	gawk

Variables

Variables are defined like var=val. They can be specified in two different places:

1. Via the -v command line flag. Using this allows accessing the variable value from within a BEGIN rule.
2. In the file list. Using this allows accessing the variable value in all subsequent file processing.

%%ANKI Basic Where in an awk invocation can variables be assigned? Back: As a -v argument or in the file list. Reference: Robbins, Arnold D. “GAWK: Effective AWK Programming,” October 2023. https://www.gnu.org/software/gawk/manual/gawk.pdf

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%%ANKI Basic The -v flag was introduced to accommodate what functionality? Back: Accessing variables from a BEGIN rule. Reference: Robbins, Arnold D. “GAWK: Effective AWK Programming,” October 2023. https://www.gnu.org/software/gawk/manual/gawk.pdf

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%%ANKI Basic Describe what the following command does in in a single sentence:

$ awk 'program' pass=1 data pass=2 data

Back: Evaluates 'program' against the data file twice with a different value of pass on each run. Reference: Robbins, Arnold D. “GAWK: Effective AWK Programming,” October 2023. https://www.gnu.org/software/gawk/manual/gawk.pdf

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%%ANKI Basic How is stdin specified in awk's file list? Back: - Reference: Robbins, Arnold D. “GAWK: Effective AWK Programming,” October 2023. https://www.gnu.org/software/gawk/manual/gawk.pdf

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References

• Robbins, Arnold D. “GAWK: Effective AWK Programming,” October 2023. https://www.gnu.org/software/gawk/manual/gawk.pdf