I thank in advance if anyone can help me. The code below: ZnClient new url: 'http://127.0.0.1:5001/add?stream-channels=true'; addPart: (ZnMimePart fieldName: 'file' fileNamed: 'file.txt'); post. generates the following response using netcat: nc -l 5001 POST /add?stream-channels=true HTTP/1.1 User-Agent: Zinc HTTP Components 1.0 Content-Length: 194 Host: 127.0.0.1:5001 Content-Type: multipart/form-data;boundary=Boundary-Zn-IDMNDZTQ Accept: */* --Boundary-Zn-IDMNDZTQ Content-Disposition: form-data;name="file";filename="file.txt" Content-Length: 16 Content-Type: text/plain;charset=utf-8 file.txt content --Boundary-Zn-IDMNDZTQ-- however I would like to get: nc -l 5001 POST /add?stream-channels=true HTTP/1.1 User-Agent: Zinc HTTP Components 1.0 Content-Length: 194 Host: 127.0.0.1:5001 Content-Type: multipart/form-data;boundary=Boundary-Zn-IDMNDZTQ Accept: */* --Boundary-Zn-IDMNDZTQ Content-Type: application/octet-stream Content-Disposition: form-data;name="file";filename="file.txt" Content-Length: 16 Content-Type: text/plain;charset=utf-8 file.txt content --Boundary-Zn-IDMNDZTQ-- I not figured out how to get the extra line "Content-Type: application / octet-stream" using Zinc. ----- http://chicoary@gmail.com -- View this message in context: http://forum.world.st/How-to-generate-Content-Type-application-octet-stream-... Sent from the Pharo Smalltalk Users mailing list archive at Nabble.com.