Protocol_GetData (changes)
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URL_Fetcher
» Protocol module interface
» Protocol_GetData
Protocol_GetData
(SWI SWI_base+0)
Start retrieving data.
| Entry | ||
|---|---|---|
| R0 | Flags | |
| Bits 0-30 | As specified by client in URL_GetURL | |
| Bit 31 | R7 is valid | |
| R1 | Session identifier | |
| R2 | Method | |
| R3 | URL (including fetch scheme) | |
| R4 | Pointer to block of data in addition to URL | |
| R5 | Protocol dependent | |
| R6 | Protocol dependent | |
| R7 | If R0:31 is set, proxy URL information | |
| Exit | ||
|---|---|---|
| R2 | Protocol status word (see URL_Status for details) | |
| All other registers are protocol-dependent. | ||
Interrupts
Interrupt status is protocol module dependent.
Re-entrancy
SWI re-entrancy is protocol module dependent.
Use
This call is used to start retrieving data. The protocol module should raise any events for the client via the session identifier provided in R1. The URL module calls this SWI in response to one of its clients calling SWI URL_GetURL.
The proxy URL information specified in R7 (if R0:31 is set) gives the location of the proxy to be used in the format of a URL. For example, “http://www-cache.demon.co.uk:8080/”. This information is supplied by the URL module and not the client. The protocol module must note that on a proxied request, the target URL indicated by R3 may not have the same fetch scheme. For example, it might be an ftp: URL being proxied through an HTTP proxy service.
Note that the session identifiers passed in R1 are not the same identifiers used by clients to talk to the URL module. They are not interchangeable.
See also
Related vectors
None
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