How to search pattern and add that pattern in next line

Shell Programming and Scripting
1

Hi All,
I am new to shell scripting and need help in scripting using CSH.
Here is what I am trying to so,

  1. Search a specific string e.g. "task" from "task (input1, out1)".
  2. Extract the arguements "input1" and "out1"
  3. Add them in separate lines below. eg. "int input1" , " integer out1"

So final output should look like,

task (input1, out1)
int input1;
integer out1;

Thanks in advance.

2

Hi

Not sure, if I got your question correctly. If so:

Input:

$ cat file
some dummy data
task (input1, out1)
some more dummy data

Output:

$ sed -r 's/task *\(([^,]+), *(.*)\)/&\nint \1;\ninteger \2;/' file
some dummy data
task (input1, out1)
int input1;
integer out1;
some more dummy data

Guru.

1 Like
3

Thanks guruprasad, you were spot on.
One more favour please, can you please tell me how that works?

4 
 
$ cat test.txt 
some dummy data
task (input1, out1)
some more dummy data
 
$ nawk -F"[)(]" '/\(/{print;n=split($2,a,",");for(i=1;i<=n;i++){printf("int %s;\n",a)}} !/\)/ {print}' test.txt
some dummy data
task (input1, out1)
int input1;
int  out1;
some more dummy data
5

We try to split the line into patterns by extracting the values "input1" and "out1". and then substituting(s) it with the original line(&), and then the first pattern preceeded by "int"(int \1 and newline) followed by second pattern(integer \2).

Guru.

6

Thanks you itkamaraj.

---------- Post updated at 01:03 PM ---------- Previous update was at 01:02 PM ----------

$ sed -r 's/task *\(([^,]+), *(.*)\)/&\nint \1;\ninteger \2;/' file
some dummy data
task (input1, out1)
int input1;
integer out1;
some more dummy data

What do I need to do to append the file instead of output on stdio?

7 
 
sed -r 's/task *\(([^,]+), *(.*)\)/&\nint \1;\ninteger \2;/' file > file.out
mv file.out file

or you can use -i

sed -i -r 's/task *\(([^,]+), *(.*)\)/&\nint \1;\ninteger \2;/' file

 
nawk -F"[)(]" '/\(/{print;n=split($2,a,",");for(i=1;i<=n;i++){printf("int %s;\n",a)}} !/\)/ {print}' test.txt > test.out
mv test.out test.txt
8

Thanks itkamraj.