We report a search for C P violation in the decay modes D ± → K 0 S K ± , D ± s → K 0 S K ± , and D ± s → K 0 S π ± using a data set corresponding to an integrated luminosity of 469     fb − 1 collected with the BABAR detector at the PEP-II asymmetric energy e + e − storage rings. The decay rate C P asymmetries, A C P , are determined to be ( + 0.13 ± 0.36 ( stat ) ± 0.25 ( syst ) ) % , ( − 0.05 ± 0.23 ( stat ) ± 0.24 ( syst ) ) % , and ( + 0.6 ± 2.0 ( stat ) ± 0.3 ( syst ) ) % , respectively. These measurements are consistent with zero, and also with the Standard Model prediction [ ( − 0.332 ± 0.006 ) % for the D ± → K 0 S K ± and D ± s → K 0 S K ± modes, and ( + 0.332 ± 0.006 ) % for the D ± s → K 0 S π ± mode]. They are the most precise determinations to date.