# PDL_ServiceCall

## Description

Makes a one-time call to a device service without a callback response.

See Accessing Services for more information and examples.

## Syntax

>     PDL_Err PDL_ServiceCall(const char *uri, const char *payload);

Argument | Description
--- | ---
uri | Service's URI (Uniform Resource Identifier). Has the form: "palm://<service name>/<service type>". For example: "palm://com.palm.applicationManager/launch" -- call the Application Manager's launch (an app) service.
payload | JSON (JavaScript Object Notation) style parameters. For example: "{ par1:"val1", par2:"val2", ...}" Note that, in C code, the inner double quotes would need to be escaped with a backslash ("\")

## Returns

>     PDL_ECONNECTION - Unable to dispatch service call.
>     PDL_NOERROR - Success.

## Example

>     PDL_err err = PDL_ServiceCall("palm://com.palm.applicationManager/launch",
>       "{ \"id\":\"com.palm.app.email\"}");

This invokes the system's Application Manager service to launch the Palm's resident email application. Note the use of the backslash character ("\") to allow using a double quote within a double quote.

See also:

- PDL_ServiceCallWithCallback
- PDL_UnregisterServiceCallback
- PDL_GetParamDouble
- PDL_GetParamInt
- PDL_GetParamString
- PDL_ParamExists