HAM_IGNORED would be the most suitable return value in your case.
You seem to have issues with return values, so here they are:
Code:
// Hamsandwich
// 0 is also interpreted as HAM_IGNORED
#define HAM_IGNORED 1 /**< Calls target function, returns normal value */
#define HAM_HANDLED 2 /**< Tells the module you did something, still calls target function and returns normal value */
#define HAM_OVERRIDE 3 /**< Still calls the target function, but returns whatever is set with SetHamReturn*() */
#define HAM_SUPERCEDE 4 /**< Block the target call, and use your return value (if applicable) (Set with SetHamReturn*()) */
// Fakemeta
#define FMRES_IGNORED 1 // Calls target function, returns normal value
#define FMRES_HANDLED 2 // Tells metamod you did something, still calls target function and returns normal value
#define FMRES_OVERRIDE 3 // Supposed to still call the target function but return your value instead
// however this does not work properly with metamod; use supercede instead.
#define FMRES_SUPERCEDE 4 // Block the target call, and use your return value (if applicable)
// Engine+Others
#define PLUGIN_CONTINUE 0 /* Results returned by public functions */
#define PLUGIN_HANDLED 1 /* stop other plugins */
#define PLUGIN_HANDLED_MAIN 2 /* to use in client_command(), continue all plugins but stop the command */
EDIT: Technically, returning PLUGIN_CONTINUE in your case would have the same effect as HAM_IGNORED, since 0 is also interpreted as HAM_IGNORED and PLUGIN_CONTINUE is defined as 0. You should still use these return values with their corresponding module forward.
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