| conc | Concurnas Source Code |
| container | Eclipse IDE Project Settings Data |
| cord | Visual Studio Cord Data |
| core | Linux Core Dump Data |
| cos | Scilab Binary Diagram |
| cosf | Scilab ASCII Diagram |
| counter | NetObjects Fusion Components Bbscomp Message |
| coverage | Visual Studio Code Coverage Data |
| cox | Click and Create Extension Object |
| cpb | CPB Data |
| cpdsc | CMSIS Pack Project Description |
| cpf | Cab Provisioning Format |
| cphd | CloudChan Pre-processed Hypertext Document |
| cpk | Novell Netware Compiled Server Software Package |
| cpl | Concordance Desktop Programming Language Script |
| cplist | GNU Make C Property-list Data |
| cplusplus | C++ Source Code |
| cplz | Crestron SIMPL# Pro Library |
| cpp | C++ Source Code |
| cpt | Concordance Compiled CPT Script |
| cpz | LoseThos C+ Source Code |
| cpz | Crestron SIMPL# Pro Program |
| cr | CRiSP Macro File |
| cr1 | CRBasic Source |
| cr2 | CRBasic Source |
| cr3 | CRBasic Source |
| cr4 | CRBasic Source |
| cr5 | CRBasic Source |
| cr6 | CRBasic Source |
| cr7 | CRBasic Source |
