FileSwitch Use Of File Types (changes)
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Programmer's FileSwitch Reference Manuals
» Part 4 – Using Filing Systems?Technical Details
» Use of File TypesFileSwitch
» Technical Details
» Use of File Types
Use of File Types
Determine the Action to Perform
As discussed in the key features section on FileSwitch, a 3-digit hexadecimal value is used to represent the file type. It is the file type that determines the action that must be performed on a file.
When a date stamped file of type xxx has an action of *Load or *Run performed on it, FileSwitch carries out several steps to determine what it should actually do.
The steps are:
- Look for the system variables
Alias$@LoadType_xxx orAlias$@RunType_xxx respectively. - If variable of string or macro type exists, then it is copied (after macro extension), and the full pathname is used to find the file on either File$Path or Run$Path
- Any parameters passed are also appended for *Run commands
- The whole string is passed to the command Line interpreter using OS_CLI
An Example of using LoadType
| File Details | |
|---|---|
| CSD | adfs::HardDisc.$.Photos.Wedding |
| Command | *LOAD Photo001 |
| File type | &FF9, Sprite (bitmap) |
| Step 1 – Find system variables | |
| Variable | *@LoadType_FF9 |
| Step 2&3 – Use full pathname + parameters | |
| Issues command | *@LoadType_FF9 adfs::HardDisc.$.Photos.Wedding.Photo001 |
Alias$@LoadType_FF9 |
has a value of SLoad %*0 by default |
| Step 4 – CLI issues command | |
| Output | *SLoad adfs::HardDisc.$.Photos.Wedding.Photo001 |
An Example of using RunType
| File Details | |||
|---|---|---|---|
| File Details | |||
| CSD | adfs::HardDisc.$.Programs | ||
| CSD | adfs::HardDisc.$.Programs |
||
| Command | *RUN BasicProg p1 p2 | ||
| Command | *RUN BasicProg p1 p2 |
||
| File type | &FFB, BASIC | ||
| File type | &FFB, BASIC | ||
| Step 1 – Find system variables | |||
| Step 1 – Find system variables | |||
| Variable | *@RunType_FFB | ||
| Variable | *@RunType_FFB |
||
| Step 2&3 – Use full pathname + parameters | |||
| Step 2&3 – Use full pathname + parameters | |||
| Issues command | *@RunType_FFB adfs::HardDisc.$.Programs.BasicProg p1 p2 | ||
| Issues command | *@RunType_FFB adfs::HardDisc.$.Programs.BasicProg p1 p2 |
||
Alias$@RunType_FFB | has a value of Basic –quit |"%0| %*1 by default | ||
Alias$@RunType_FFB |
has a value of Basic –quit |
“%0 | %*1 by default |
| Step 4 – CLI issues command | |||
| Step 4 – CLI issues command | |||
| Output | *Basic - quit "adfs::HardDisc.$.Programs.BasicProg" p1 p2 | ||
| Output | *Basic - quit "adfs::HardDisc.$.Programs.BasicProg" p1 p2 |
||
Default Settings
The filing system manager sets several of these system variables by default; however, they can be changed easily. This is useful say, if a newly installed application wants to be responsible for loading files of a certain type.
Setting a file of a specific file type can easily be achieved by using the *Set command.
A simple example of this is command is provided below.
Set Alias$@LoadType_007 SpyApp %*0
Set Alias$@RunType_007 SpyApp %*0
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