使用awk或sed在文件中动态替换字符串

Question

I have a need to replace filename in a file to a string which is cp command and hence it should replace existing filename with cp source destination in same file .file is comma separated #m sample file

ABC,TS-R:56:UT-123,/apps/home/t.txt
ICA,Y6734YGSU,/apps/home/t2.txt
MDI,UI-HDGD-PO567,/apps/home/t3.txt

now i want a sed or awk command which can replace the /apps/home/<filename>.txt to cp /apps/home/<filename>.txt /apps/cmb/<filename>.txt

so after sed/awk same file should have contents

ABC,TS-R:56:UT-123,cp /apps/home/t.txt /apps/cmb/t.txt
ICA,Y6734YGSU,cp /apps/home/t2.txt /apps/cmb/t2.txt
MDI,UI-HDGD-PO567,cp /apps/home/t3.txt /apps/cmb/t3.txt

I tried awk -F, '{$3="cp "$3" "$3""}1' OFS=, test.txt but its just printing ABC,TS-R:56:UT-123,cp /apps/home/t.txt /apps/home/t.txt also in console and not changing in file.

Thanks in advance .

Answer 1

This should do:

awk -F/ '{print $1"cp ",$2,$3,$4 " ",$2,"cmb",$4}' OFS=/ file
ABC,TS-R:56:UT-123,cp /apps/home/t.txt /apps/cmb/t.txt
ICA,Y6734YGSU,cp /apps/home/t2.txt /apps/cmb/t2.txt
MDI,UI-HDGD-PO567,cp /apps/home/t3.txt /apps/cmb/t3.txt

Answer 2

You can use awk:

awk -F, -v OFS=, '{p=$NF; sub(/\/home\//, "/cmb/", $NF); 
     $NF=sprintf("cp %s %s", p, $NF)} 1' file
ABC,TS-R:56:UT-123,cp /apps/home/t.txt /apps/cmb/t.txt
ICA,Y6734YGSU,cp /apps/home/t2.txt /apps/cmb/t2.txt
MDI,UI-HDGD-PO567,cp /apps/home/t3.txt /apps/cmb/t3.txt

Answer 3

Since this is simple substitutions on individual lines it'd be an appropriate job for sed:

$ sed -r 's:(/[^/]+/)([^/]+)(/[^/]+):cp & \1cmb\3:' file
ABC,TS-R:56:UT-123,cp /apps/home/t.txt /apps/cmb/t.txt
ICA,Y6734YGSU,cp /apps/home/t2.txt /apps/cmb/t2.txt
MDI,UI-HDGD-PO567,cp /apps/home/t3.txt /apps/cmb/t3.txt