replace string with patterns in file

I've used sed to replace variables on *.go files using sed -i 's/\<old_name\>/newName/g' *.go My objective is to eliminate golinter errors. How can strings with common patterns, e.g. replace 1 with 2

1. fmt.Printf("blah blah blah") or fmt.Printf("yadda yadda yadda")
2. fmt.Println("blah blah blah") or fmt.Println("yadda yadda yadda")

In this case, we do NOT want to replace: 1. fmt.Printf("print speed= %d",speed) //So the key here is the ending pattern should be "). 2. log.Printf statements //only replace "fmt." Any pointers on this?

I'm slightly confused by your question, but think you're trying to do the following:

replace      printf("yada yada yada") with println("yada yada yada")
not replace  printf("print speed = %d", speed)

If that is the case, I would do something like the following:

sed -i '/Printf(\".*\")/ s/Printf/Println/g' *.go

That should leave cases intact where you actually want to use formatting. Here is an example:

[sborza@msandn]:~$ cat tester.go
package main

import "fmt"

func main() {
        speed = 1
        fmt.Printf("vim-go")
        fmt.Printf("speed = %d\n", speed)
}

[sborza@msandn]:~$ sed '/Printf(\".*\")/ s/Printf/Println/g' tester.go
package main

import "fmt"

func main() {
        speed = 1
        fmt.Println("vim-go")
        fmt.Printf("speed = %d\n", speed)
}