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Replacing the last occurence of a expression in every line

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Top Forums Shell Programming and Scripting Replacing the last occurence of a expression in every line
# 1  
Old 02-15-2010
Replacing the last occurence of a expression in every line
I have a file which contains

Code:
 
/RdWrCtrl/IRdWrRepCtl/XI3/XIrdOutEnRdSbComb\[0\]/XRdDataGaterEnx
/RdWrCtrl/IRdWrRepCtl/XI3/XIrdOutEnRdSbComb\[1\]/XRdDataGaterEnx
/RdWrCtrl/IRdWrRepCtl/XI3/XIrdOutEnRdSbComb\[2\]/XRdDataGaterEnx
/RdWrCtrl/IRdWrRepCtl/XI3/XIrdOutEnRdSbComb\[3\]/XRdDataGaterEnx


I have to replace the last occurence of /X in each line
ie I need my output

Code:
 
/RdWrCtrl/IRdWrRepCtl/XI3/XIrdOutEnRdSbComb\[0\]/RdDataGaterEnx
/RdWrCtrl/IRdWrRepCtl/XI3/XIrdOutEnRdSbComb\[1\]/RdDataGaterEnx
/RdWrCtrl/IRdWrRepCtl/XI3/XIrdOutEnRdSbComb\[2\]/RdDataGaterEnx
/RdWrCtrl/IRdWrRepCtl/XI3/XIrdOutEnRdSbComb\[3\]/RdDataGaterEnx

Please suggest me a way to do the same..

Thnx
Naveen
# 2  
Old 02-15-2010
Code:
awk -F "" '{$(NF-14)=""}1 ' OFS="" input.txt

# 3  
Old 02-15-2010
How did you get the 14? Is it generic ? If I have varied string lengths like

Code:
/RdWrCtrl/IRdWrRepCtl/XI3/XIrdOutEnRdSbComb\[0\]/XRdDataGaterEnx
/IRdWrRepCtl/XI3/XIrdOutEnRdSbComb\[1\]/XRdDataGaterEnx
/RdWrCtrl/IRdWrRepCtl/XI3/XIrdOutEnRdSbComb\[2\]/XRdDataGaterEnx
/RdWrCtrl/IRdWrRepCtl/XI3/XIrdOutEnRdSbComb\[3\]/XRdDataGaterEnx

will this work??

THanks

---------- Post updated at 04:28 PM ---------- Previous update was at 04:23 PM ----------

And the code doesnt work for the last line as there are 3 additional characters

---------- Post updated at 04:30 PM ---------- Previous update was at 04:28 PM ----------

ie if i have

Code:
/RdWrCtrl/IRdWrRepCtl/XI3/XIrdOutEnRdSbComb\[0\]/XRdDataGaterEnx
/IRdWrRepCtl/XI3/XIrdOutEnRdSbComb\[1\]/XRdDataGaterEnx
/RdWrCtrl/IRdWrRepCtl/XI3/XIrdOutEnRdSbComb\[2\]/XRdDataGaterEnx
/RdWrCtrl/IRdWrRepCtl/XI3/XIrdOutEnRdSbComb\[3\]/XRdDataGaterEnxEnx

then 14 will not work right? So is there any other way out?
# 4  
Old 02-15-2010
Code:
 sed 's/X//3' input.txt

# 5  
Old 02-15-2010
I am very very sorry should have given a proper code...

Can you suggest one last time

what if I have

Code:
/RdWrCtrl/IRdWrRepCtl/XI3/XIrdOutEnRdSbComb\[0\]/XRdDataGaterEnx
/IRdWrRepCtl/XI3/XIrdOutEnRdSbComb\[1\]/XRdDataGaterEnx
/RdWrCtrl/IRdWrRepCtl/I3/XIrdOutEnRdSbComb\[2\]/XRdDataGaterEnx
/RdWrCtrl/IRdWrRepCtl/XI3/XIrdOutEnRdSbComb\[3\]/XRdDataGaterEnxEnx

I need the output


Code:
/RdWrCtrl/IRdWrRepCtl/XI3/XIrdOutEnRdSbComb\[0\]/RdDataGaterEnx
/IRdWrRepCtl/XI3/XIrdOutEnRdSbComb\[1\]/RdDataGaterEnx
/RdWrCtrl/IRdWrRepCtl/I3/XIrdOutEnRdSbComb\[2\]/RdDataGaterEnx
/RdWrCtrl/IRdWrRepCtl/XI3/XIrdOutEnRdSbComb\[3\]/RdDataGaterEnxEnx

basically all i need to do is replace the last occurence of /X with /
# 6  
Old 02-15-2010
Code:
sed -e 's/\(.*\)\/X\(.*\)$/\1\/\2/g' abc.txt


HTH,
PL
# 7  
Old 02-15-2010
yes that helps could you please explain the code?? Thnks so much
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