---
title: CMSEncoderSetEncapsulatedContentType
framework: security
role: symbol
role_heading: Function
path: security/cmsencodersetencapsulatedcontenttype
---

# CMSEncoderSetEncapsulatedContentType

Specifies an object identifier for the encapsulated data of a signed message.

## Declaration

```occ
OSStatus CMSEncoderSetEncapsulatedContentType(CMSEncoderRef cmsEncoder, const SecAsn1Oid *eContentType);
```

## Parameters

- `cmsEncoder`: The CMSEncoder reference returned by the CMSEncoderCreate function.
- `eContentType`: The object identifier for the encapsulated data in a signed message.

## Return Value

Return Value A result code. See Security Framework Result Codes.

## Discussion

Discussion In a signed message, the signed data consists of any type of content (referred to as the encapsulated content, because it is encapsulated in the signed data) plus the signature values. You can indicate the content type of the encapsulated data by specifying an object identifier (OID) in the eContentType parameter of this function. The default value for the OID (used if this function is not called) is id-data. This is the normal encapsulated content type for applications such as S/MIME, which uses it to indicate MIME-encoded content. You can pass any value that is meaningful to your application. Examples of CMS OIDs are listed in http://www.imc.org/ietf-smime/other-smime-oids.asn. If you do call this function, you must call it before the first call to the CMSEncoderUpdateContent function. Special Considerations Use CMSEncoderSetEncapsulatedContentTypeOID(_:_:) for new development.

## See Also

### Related Documentation

- [CMSDecoderCopyEncapsulatedContentType(_:_:)](security/cmsdecodercopyencapsulatedcontenttype(_:_:).md)
- [CMSEncoderUpdateContent(_:_:_:)](security/cmsencoderupdatecontent(_:_:_:).md)
- [CMSEncoderCreate(_:)](security/cmsencodercreate(_:).md)
- [CMSEncoderCopyEncapsulatedContentType(_:_:)](security/cmsencodercopyencapsulatedcontenttype(_:_:).md)