Why not use something like GNU grep? It's strictly command-line, and it can be set for silent mode too. Download and/or read documentation at: <http://www.gnu.org/software/grep/>
But if you want an app that provides an easy-to-use GUI for building & saving sets of search-replace operations -- which you can then call from a command-line -- consider BK ReplaceEm.
This 32-bit Windows freeware application hasn't been supported or distributed by its developer Bill Klein (BK) for a number of years. But it was once considered among the very best search-n-replace apps (free or not). And I think it still deserves such consideration.
For a rather complicated example of the very sort which originally inspired BK to create his application, see: <http://www.ccp14.ac.uk/ccp14admin/bkreplacem/index.html>.
But the download URL on the latter webpage is dead. To download it, you must use an archive website like SnapFiles: <http://files.snapfiles.com/localdl834/bkrep20.exe>.
It's a very safe program to install & try -- it just puts its files in a single folder w/o any changes to the registry, as I recall.
With BK ReplaceEm, you use replace groups and file sets.
A replace group consists of a series of search & replace strings (regular expressions & 'range replacements' are supported, and any series of simple boolean operations can be input & saved via the GUI too).
A file set consists of a single file, multiple files, or a whole directory -- perhaps filtered by particular file extensions. Whatever.
You can have the program create a backup copy of every file it operates on, in case things don't go as you expected.
You can have the program output to different locations too. And if you want, you can set the application to run additional -- and different -- replacement operations on all files found in that second location. Logs can be generated too.
I hope that's an accurate description. It's a been a while since I've used it. I invested in the very expensive TextPipe Pro a couple years ago, which, I think is the application BK ReplaceEm most resembles.
BTW, anyone interested in search & replacement operations would be well-served by Friedl's book, 'Mastering Regular Expressions', now in its 3rd edition from O'Reilly. I'm not a programmer, but this book has helped me greatly in parsing & editing text, in website development & maintenance, even in finding & managing files on my desktop PC -- all via the numerous applications that now support Perl & other varieties (like grep) of regular expressions.