How to replace colon in HH:MI:SS to hypen?

Shell Programming and Scripting
1

I have a file that contains timestamp in some of the rows in the file and the field separator is colon and some of the rows have numerical values, timestamp and characters with colon as the field separator
We are looking to change colon in HH:MI:SS for the timestamp to hyphen �-� leaving the field separator untouched. Below is a sample data.

Code:

20189:wf_boat_extracts: invalid string: 20897:78:08/15/2014 10:20:54:state:country:

After formatting the data should be in this format.

Code:

20189:wf_boat_extracts: invalid string: 20897:78:08/15/2014 10-20-54:state:country:

Any suggestion will be really appreciated.

Thanks,
Cumeh1624

2

Try:

sed 's/\( [0-2][0-9]\):\([0-5][0-9]\):\([0-9][0-9]\):/\1-\2-\3:/' file