Swap the appearance order of two lines if needed.
in [Shell]
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From: Hongyi Zhao on 26 Nov 2009 21:16 On Thu, 26 Nov 2009 13:37:15 -0800 (PST), w_a_x_man <w_a_x_man(a)yahoo.com> wrote: >Yes. >ruby -i.bak -pe'gsub( "c", "x" )' data > >This makes a backup file named "data.bak" and replaces >each "c" with "x". Good, thanks again. I want to do the inplace edit without backup file generated. What option should I use? -- ..: Hongyi Zhao [ hongyi.zhao AT gmail.com ] Free as in Freedom :.
From: Rakesh Sharma on 27 Nov 2009 04:52 On Nov 26, 7:33 am, Hongyi Zhao <hongyi.z...(a)gmail.com> wrote: > On Tue, 24 Nov 2009 12:22:17 -0800 (PST), Rakesh Sharma > > <sharma...(a)hotmail.com> wrote: > >Provided there's atleast one line between line_a & line_b we can do > >this: > > In my case, the line_b sometimes just immediately appear before > line_a, i.e., > > line_b > line_a > > How should your code be changed in order to deal with both cases? > > > > >sed -e ' > > /\n/b > > /re1/,/re2/!b > > /re2/!H;/re1/h;/re2/!d > > p;g;s/\n.*//;H;g;D > >' yourfile > > So complicated for me to understand, any hints on your code? > > Best regards. > -- > .: Hongyi Zhao [ hongyi.zhao AT gmail.com ] Free as in Freedom :. As you have stated that you want to align line_a then line_b no matter where they come in the file. & they occur just once in the file. sed -ne ' /line_a/ba /line_b/bb p;d :a p;n;/line_b/bspin :notb /line_b/!{ H;n bnotb } p;g;s/.//;bspin :b h;n :nota /line_a/!{ p;n bnota } G;bspin :spin p;$d;n bspin ' yourfile -- Rakesh
From: WANG Cong on 27 Nov 2009 10:41 On 11/26/09 11:51, Hongyi Zhao <hongyi.zhao(a)gmail.com> wrote: > On Wed, 25 Nov 2009 21:02:04 -0600, Ed Morton <mortonspam(a)gmail.com> > wrote: > >>So, is there actually any swapping involved or do you just want to save line_a >>and print it before line_b? > > 1- If line_b appears just immediately after line_a, then do nothing. > > 2- In other cases, move line_b to make sure it just immediately after > line_a > awk 'BEGIN{a=b=i=0}/line_a/{a=i;} /line_b/{b=i;} {l[i++]=$0;} END{t=l[b];for(i=0;i<NR;i++){if(i!=b)print l[i];if(i==a)print t;}}' your_file -- Live like a child, think like the god.
From: WANG Cong on 27 Nov 2009 10:42 On 11/27/09 10:16, Hongyi Zhao <hongyi.zhao(a)gmail.com> wrote: > On Thu, 26 Nov 2009 13:37:15 -0800 (PST), w_a_x_man > <w_a_x_man(a)yahoo.com> wrote: > >>Yes. >>ruby -i.bak -pe'gsub( "c", "x" )' data >> >>This makes a backup file named "data.bak" and replaces >>each "c" with "x". > > Good, thanks again. I want to do the inplace edit without backup file > generated. What option should I use? '-i' without anything, the same as 'sed'. -- Live like a child, think like the god.
From: Hongyi Zhao on 27 Nov 2009 21:01
On Fri, 27 Nov 2009 23:42:27 +0800, WANG Cong <xiyou.wangcong(a)gmail.com> wrote: >'-i' without anything, the same as 'sed'. Does the gets(nil) statement work with '-i' switch? In my case, I always meet the error like this: test.rb:9:in `gets': Can't do inplace edit without backup (fatal) from test.rb:9 Why? -- ..: Hongyi Zhao [ hongyi.zhao AT gmail.com ] Free as in Freedom :. |