Sed & Awk, 2/e (Paperback)

Dale Dougherty, Arnold Robbins

  • 出版商: O'Reilly
  • 出版日期: 1997-04-08
  • 定價: $1,800
  • 售價: 9.0$1,620
  • 語言: 英文
  • 頁數: 434
  • 裝訂: Paperback
  • ISBN: 1565922255
  • ISBN-13: 9781565922259
  • 相關分類: Command Line程式語言
  • 立即出貨 (庫存 < 3)

買這商品的人也買了...

商品描述

sed & awk describes two text processing programs that are mainstays of the UNIX programmer's toolbox.

sed is a "stream editor" for editing streams of text that might be too large to edit as a single file, or that might be generated on the fly as part of a larger data processing step. The most common operation done with sed is substitution, replacing one block of text with another.

awk is a complete programming language. Unlike many conventional languages, awk is "data driven" -- you specify what kind of data you are interested in and the operations to be performed when that data is found. awk does many things for you, including automatically opening and closing data files, reading records, breaking the records up into fields, and counting the records. While awk provides the features of most conventional programming languages, it also includes some unconventional features, such as extended regular expression matching and associative arrays. sed & awk describes both programs in detail and includes a chapter of example sed and awk scripts.

This edition covers features of sed and awk that are mandated by the POSIX standard. This most notably affects awk, where POSIX standardized a new variable, CONVFMT, and new functions, toupper() and tolower(). The CONVFMT variable specifies the conversion format to use when converting numbers to strings (awk used to use OFMT for this purpose). The toupper() and tolower() functions each take a (presumably mixed case) string argument and return a new version of the string with all letters translated to the corresponding case.

In addition, this edition covers GNU sed, newly available since the first edition. It also updates the first edition coverage of Bell Labs nawk and GNU awk (gawk), covers mawk, an additional freely available implementation of awk, and briefly discusses three commercial versions of awk, MKS awk, Thompson Automation awk (tawk), and Videosoft (VSAwk).

 

商品描述(中文翻譯)

《sed & awk》描述了兩個文本處理程序,它們是UNIX程序員工具箱中的主要工具。

sed是一個“流編輯器”,用於編輯可能太大而無法作為單個文件編輯的文本流,或者作為更大數據處理步驟的一部分即時生成的文本流。最常用的sed操作是替換,將一塊文本替換為另一塊文本。

awk是一個完整的編程語言。與許多傳統語言不同,awk是“數據驅動”的 - 您指定您感興趣的數據類型以及在找到該數據時要執行的操作。awk為您做了很多事情,包括自動打開和關閉數據文件,讀取記錄,將記錄分解為字段,並計算記錄數。雖然awk提供了大多數傳統編程語言的功能,但它還包括一些非傳統功能,例如擴展的正則表達式匹配和關聯數組。《sed & awk》詳細描述了這兩個程序,並包括一章節的示例sed和awk腳本。

本版涵蓋了POSIX標準規定的sed和awk功能。這對awk影響最大,其中POSIX標準化了一個新變量CONVFMT和新函數toupper()和tolower()。CONVFMT變量指定在將數字轉換為字符串時要使用的轉換格式(awk以前使用OFMT進行此操作)。toupper()和tolower()函數分別接受一個(可能是混合大小寫的)字符串參數,並返回一個所有字母轉換為相應大小寫的新版本字符串。

此外,本版還涵蓋了自第一版以來新推出的GNU sed。它還更新了第一版對Bell Labs nawk和GNU awk(gawk)的覆蓋範圍,涵蓋了mawk,這是awk的另一個免費可用實現,並簡要討論了三個商業版本的awk,MKS awk,Thompson Automation awk(tawk)和Videosoft(VSAwk)。