[Home](./index.md) > [ibm-cloud-sdk-core](./ibm-cloud-sdk-core.md) > [isFileData](./ibm-cloud-sdk-core.isfiledata.md) ## isFileData() function **Signature:** ```typescript export declare function isFileData(obj: any): obj is NodeJS.ReadableStream | Buffer; ``` ## Parameters

Parameter	Type	Description
obj	any

**Returns:** obj is NodeJS.ReadableStream \| Buffer