GET (TCP/IP statement)
Jump to navigation
Jump to search
Navigation:
GET reads unformatted (raw) data from an open TCP/IP connection opened with _OPENCLIENT, _OPENHOST or _OPENCONNECTION.
Contents
Syntax
Syntax 1:
- GET #handle, , b$
- Reads any available data into variable length string b$ (b$'s length is adjusted to the number of bytes read, so checking EOF is unnecessary) using the handle return value from _OPENCLIENT, _OPENHOST or _OPENCONNECTION.
Syntax 2:
- GET #handle, ,x%
- Reads an integer. If 2 bytes are available, they are read into x%, if not then nothing is read and EOF(handle) will return -1 (and x%'s value will be undefined) using the handle return value from _OPENCLIENT, _OPENHOST or _OPENCONNECTION.
Communicating using unformatted/raw streamed data
- Benefit: Communicate with any TCP/IP compatible protocol (eg. FTP, HTTP, web-pages, etc).
- Disadvantage: Streamed data has no 'message length', as such just the program deals with a continuous number of bytes in a row. Some messages get fragmented and parts of messages can (and often do) arrive at different times, due to the very nature of the TCP/IP protocol.
- The position parameter (between the commas) is not used in TCP/IP connections.
- The programmer must cater for these situations manually.
Examples
Example:
PUT #c, , a$ ' sends data GET #o, , b$ ' reads any available data into variable length string b$ GET #o, , x% ' if 2 bytes are available, they are read into x%
Explanation:
- Data could be a string, variable array, user defined TYPE, etc.
- b$'s length is adjusted to the number of bytes read. Checking EOF(o) is unnecessary.
- If 2 bytes are not available for the x% integer then nothing is read and EOF(o) will return -1
More examples
- See the examples in _OPENCLIENT or Email Demo.
See also
- PUT (TCP/IP statement)
- _OPENCLIENT, _OPENHOST
- _OPENCONNECTION, GET #
- cURL (HTTP and FTP file transfer)
