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# 1  
Old 12-30-2018
Replace last n lines
Dear Friends,

Using centos 7 version.. I have a file content like this

Code:
if bld.env.SAMBA_DIR:
    bld.program(target='winexe-static',
        source='winexe.c svcinstall.c async.c winexesvc32_exe.c winexesvc64_exe.c',
        includes=bld.env.SAMBA_DIR + '/bin/default/include/public',
        cflags='-pthread -include ' + bld.env.SAMBA_DIR + '/bin/default/include/config.h',
        linkflags='-pthread',
        stlibpath=bld.srcnode.abspath() + '/smb_static/build',
        stlib='smb_static bsd z resolv rt',
        lib='dl gnutls'
        )

Where I need to replace last but two line to below
Code:
        stlib='smb_dynamic bsd z resolv rt',
        lib='dl ls'

how can i do it with unix command instead of manually editing file.

thanks in advance
# 2  
Old 12-30-2018
Hello onenessboy,

Could you please try following once.

Code:
tac Input_file | awk 'FNR==2{sub("static","dynamic")} FNR==3{sub("gnutls","ls")} 1' | tac

In case you want to save output into Input_file itself then append > temp_file && mv temp_file Input_file in above code too.

Thanks,
R. Singh
These 2 Users Gave Thanks to RavinderSingh13 For This Post:
Neo onenessboy
# 3  
Old 12-30-2018
Quote:
Originally Posted by RavinderSingh13
Hello onenessboy,

Could you please try following once.

Code:
tac Input_file | awk 'FNR==2{sub("static","dynamic")} FNR==3{sub("gnutls","ls")} 1' | tac

In case you want to save output into Input_file itself then append > temp_file && mv temp_file Input_file in above code too.

Thanks,
R. Singh
Hi Ravinder,

Thanks much for help, but is there any way that we can replace nth line without any conditions to check ? as your solution checking for strings and then replace, but is there any way, I can directly remove last but two lines and replace entire line as per my previous post ? what I mean remove completely last but two line before in that input file and append/replace these two lines in that place. The reason being stlib value may contain another strings also at times so wanted to remove that line and append
Code:
stlib='smb_dynamic bsd z resolv rt',
lib='dl ls'

Last edited by onenessboy; 12-30-2018 at 07:46 AM..
# 4  
Old 12-30-2018
Quote:
Originally Posted by onenessboy
Hi Ravinder,

Thanks much for help, but is there any way that we can replace nth line without any conditions to check ? as your solution checking for strings and then replace, but is there any way, I can directly remove last but two lines and replace entire line as per my previous post ? what I mean remove completely last but two line before in that input file and append/replace these two lines in that place
Code:
stlib='smb_dynamic bsd z resolv rt',
lib='dl ls'

You could THANK people by hitting THANKS button on left corner of each post. Could you please try following.

Code:
tac Input_file | awk 'FNR!=2 && FNR!=3' | tac

Let me know if this helps you.

Thanks,
R. Singh
This User Gave Thanks to RavinderSingh13 For This Post:
onenessboy
# 5  
Old 12-30-2018
Quote:
Originally Posted by RavinderSingh13
You could THANK people by hitting THANKS button on left corner of each post. Could you please try following.

Code:
tac Input_file | awk 'FNR!=2 && FNR!=3' | tac

Let me know if this helps you.

Thanks,
R. Singh
Hi Ravinder,

I tried your solution here is what it displays..
stlib='smb_static bsd z resolv rt' this line still shows..
Code:
[root@xx-xx--xxx source]# tac reptest | awk 'FNR!=2 && FNR!=3' | tac
if bld.env.SAMBA_DIR:
    bld.program(target='winexe-static',
        source='winexe.c svcinstall.c async.c winexesvc32_exe.c winexesvc64_exe.c',
        includes=bld.env.SAMBA_DIR + '/bin/default/include/public',
        cflags='-pthread -include ' + bld.env.SAMBA_DIR + '/bin/default/include/config.h',
        linkflags='-pthread',
        stlibpath=bld.srcnode.abspath() + '/smb_static/build',
        stlib='smb_static bsd z resolv rt',

mean while i am trying head command too...let you know result
# 6  
Old 12-30-2018
Hello onenessboy,

It is working fine for me as follows. I am attaching screen shot for same too.
Since NOT able to copy/paste screen shot here.

Thanks,
R. Singh
This User Gave Thanks to RavinderSingh13 For This Post:
onenessboy
# 7  
Old 12-30-2018
Quote:
Originally Posted by onenessboy
Hi Ravinder,

I tried your solution here is what it displays..
stlib='smb_static bsd z resolv rt' this line still shows..
Code:
[root@xx-xx--xxx source]# tac reptest | awk 'FNR!=2 && FNR!=3' | tac
if bld.env.SAMBA_DIR:
    bld.program(target='winexe-static',
        source='winexe.c svcinstall.c async.c winexesvc32_exe.c winexesvc64_exe.c',
        includes=bld.env.SAMBA_DIR + '/bin/default/include/public',
        cflags='-pthread -include ' + bld.env.SAMBA_DIR + '/bin/default/include/config.h',
        linkflags='-pthread',
        stlibpath=bld.srcnode.abspath() + '/smb_static/build',
        stlib='smb_static bsd z resolv rt',

mean while i am trying head command too...let you know result
Ok, as of now I figured it out with different command that is head -n to remove last 3 lines and append new lines with >>

Code:
[root@ip-xxxxx source]# head -n -3 reptest > tmp.txt && cp tmp.txt reptest
cp: overwrite ‘reptest'? y
[root@ip-xxxxxx source]# echo -e '\t'"stlib='smb_dynamic bsd z resolv rt'", >> reptest
[root@ip-xxxxxx source]# echo -e '\t'"lib='dl ls'", >> reptest
[root@ip-xxxxxx source]# echo -e '\t'")" >> reptest
[root@ip-xxxxx source]# cat reptest
if bld.env.SAMBA_DIR:
    bld.program(target='winexe-static',
        source='winexe.c svcinstall.c async.c winexesvc32_exe.c winexesvc64_exe.c',
        includes=bld.env.SAMBA_DIR + '/bin/default/include/public',
        cflags='-pthread -include ' + bld.env.SAMBA_DIR + '/bin/default/include/config.h',
        linkflags='-pthread',
        stlibpath=bld.srcnode.abspath() + '/smb_static/build',
        stlib='smb_dynamic bsd z resolv rt',
        lib='dl ls',
        )

This User Gave Thanks to onenessboy For This Post:
RavinderSingh13
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