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Q213970

AWK () is a scripting language designed for text processing and typically used as a data extraction and reporting tool. Like sed and grep, it is a filter, and it is a standard feature of most Unix-like operating systems. The shell command that runs the AWK processor is named .

Key facts

Programming language.screenshot caption: Usage of AWK in shell to check matching fields in two files
Programming language.logo: The-AWK-Programming-Language.svg
Programming language.logo_size: 200px
Programming language.screenshot: Awk-example-usage-gimp.gif
Programming language.screenshot_size: 250px
Programming language.name: AWK
Programming language.paradigm: Scripting, procedural, data-driven
Programming language.latest_release_version: IEEE Std 1003.1-2008 (POSIX) / 1985
Programming language.designer: Alfred Aho, Peter Weinberger, and Brian Kernighan
Programming language.typing: none; can handle strings, integers and floating-point numbers; regular expressions
Programming language.implementations: awk, GNU Awk, mawk, nawk, MKS AWK, Thompson AWK (compiler), Awka (compiler)
Programming language.dialects: old awk oawk 1977, new awk nawk 1985, GNU Awk gawk
Programming language.influenced_by: C, sed, SNOBOL
Programming language.influenced: Tcl, AMPL, Perl, Korn Shell (ksh93, dtksh, tksh), Lua
Programming language.operating_system: Cross-platform

via Wikipedia infobox

Article

23 sections

Contents

History
Structure of AWK programs
Commands
The ''print'' command
Built-in variables
Variables and syntax
User-defined functions
Examples
Hello, World!
Print lines longer than 80 characters
Count words
Sum last word
Match a range of input lines
Printing the initial or the final part of a file
Calculate word frequencies
Match pattern from command line
Self-contained AWK scripts
Versions and implementations
Books
See also
References
Further reading
External links

The AWK language is a data-driven scripting language consisting of a set of actions to be taken against streams of textual data – either run directly on files or used as part of a pipeline – for purposes of extracting or transforming text, such as producing formatted reports. The language extensively uses the string datatype, associative arrays (that is, arrays indexed by key strings), and regular expressions. While AWK has a limited intended application domain and was especially designed to support one-liner programs, the language is Turing-complete, and even the early Bell Labs users of AWK often wrote well-structured large AWK programs.