Shell Programming Four Musketeers practice--awk

Awk is a powerful text analysis tool, with the search for grep and the editing of SED, which is especially powerful when it comes to analyzing data and generating reports. To put it simply, awk reads the file line-by-row, using spaces as the default delimiter to slice each row, and then perform various analytical processing of the cut.

AWK has 3 different versions: AWK, Nawk, and gawk, which are not specifically described, generally referred to as the GNU version of awk, Gawk,gawk.

AWK is the abbreviation for three names: Aho, Peter Weinberg and (Brain) Kernighan. It was these three people who created awk---an excellent scanning and processing tool for style.

A few simple applications:

1. Show a Byte

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2. Show only users in/etc/passwd

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Displays the shell for the account and account, and the TAB key between the account and the shell

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3. Retrieving IP

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4. Retrieving the usage of the root directory "/"

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This article is from the "Records" blog, so be sure to keep this source http://lwj421.blog.51cto.com/7119945/1738251

Shell Programming Four Musketeers practice--awk