[sed & awk] 混合使用 sed and awk 尋找

nameState 所泄生的輸出被接管送到 awk 程式，以便抽取出每筆紀錄。

list

root@ubuntu:/media/sf_share/sedawk_progs/sedawk2progs/ch02# cat list John Daggett, 341 King Road, Plymouth MA Alice Ford, 22 East Broadway, Richmond VA Orville Thomas, 11345 Oak Bridge Road, Tulsa OK Terry Kalkas, 402 Lans Road, Beaver Falls PA Eric Adams, 20 Post Road, Sudbury MA Hubert Sims, 328A Brook Road, Roanoke VA Amy Wilde, 334 Bayshore Pkwy, Mountain View CA Sal Carpenter, 73 6th Street, Boston MA

nameState

s/ CA/, California/ s/ MA/, Massachusetts/ s/ OK/, Oklahoma/ s/ PA/, Pennsylvania/ s/ VA/, Virginia/

結果

root@ubuntu:/media/sf_share/sedawk_progs/sedawk2progs/ch02# sed -f nameState list | awk -F, '{print $4}' Massachusetts Virginia Oklahoma Pennsylvania Massachusetts Virginia California Massachusetts

列出每一個州名，並在其後印出每一個居民的名字。

這個 shell 命令稿分成三部分

首先呼叫 awk 以產生待排序的資料，當作 sort 之輸入

再呼叫 awk 測試排序好的輸入資料，以判斷當前紀錄中的州名是否與先前的紀錄重覆

byState

#! /bin/sh awk -F, '{ print $4 ", " $0 }' $* | sort | awk -F, ' $1 == LastState { print "\t" $2 } $1 != LastState { LastState = $1 print $1 print "\t" $2 }'

 

root@ubuntu:/media/sf_share/sedawk_progs/sedawk2progs/ch02# sed -f nameState list | ./byState California Amy Wilde Massachusetts Eric Adams John Daggett Sal Carpenter Oklahoma Orville Thomas Pennsylvania Terry Kalkas Virginia Alice Ford Hubert Sims

工作原理

root@ubuntu:/media/sf_share/sedawk_progs/sedawk2progs/ch02# sed -f nameState list | awk -F, '{print $4 ", " $0}' Massachusetts, John Daggett, 341 King Road, Plymouth, Massachusetts Virginia, Alice Ford, 22 East Broadway, Richmond, Virginia Oklahoma, Orville Thomas, 11345 Oak Bridge Road, Tulsa, Oklahoma Pennsylvania, Terry Kalkas, 402 Lans Road, Beaver Falls, Pennsylvania Massachusetts, Eric Adams, 20 Post Road, Sudbury, Massachusetts Virginia, Hubert Sims, 328A Brook Road, Roanoke, Virginia California, Amy Wilde, 334 Bayshore Pkwy, Mountain View, California Massachusetts, Sal Carpenter, 73 6th Street, Boston, Massachusetts

預設的狀況下，程式 sort 會依字母順序排序每個輸入列，並從左到右檢視其中每個字元。

root@ubuntu:/media/sf_share/sedawk_progs/sedawk2progs/ch02# sed -f nameState list | awk -F, '{print $4 ", " $0}' | sort California, Amy Wilde, 334 Bayshore Pkwy, Mountain View, California Massachusetts, Eric Adams, 20 Post Road, Sudbury, Massachusetts Massachusetts, John Daggett, 341 King Road, Plymouth, Massachusetts Massachusetts, Sal Carpenter, 73 6th Street, Boston, Massachusetts Oklahoma, Orville Thomas, 11345 Oak Bridge Road, Tulsa, Oklahoma Pennsylvania, Terry Kalkas, 402 Lans Road, Beaver Falls, Pennsylvania Virginia, Alice Ford, 22 East Broadway, Richmond, Virginia Virginia, Hubert Sims, 328A Brook Road, Roanoke, Virginia

為了依照州名順序重新排列紀錄，因此我們將州名加到每筆紀錄的起頭，當作排序的關鍵欄位。

配合 SVN ST

svn st | awk '{if ( $1 == "M") { print $0}}'