I have a Linux C program I'm writing that has one section where, within a large string, I need to substitute a smaller string for another, and those probably won't be the same size.

For instance, if I have a string:

"Nowisthetimeforallgoodmen"

and I want to substitute 'most' for 'all' the main string will increase in size:

"Nowisthetimeformostgoodmen"


or a substitution that will increase the size of the main string:

"Nowisthetimefornogoodmen"


I thought I might get some opinions about what might be the best approach on something like this, besides some more cumbersome way of doing it. I've been looking at the C string functions to see if there's one that might be helpful, but I don't really see any.

Any help would be appreciated.