2019-04-16 13:36:57 -04:00
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# User applications
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2019-05-19 11:19:41 -04:00
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This folder contains code designed to be "userspace" application. Unlike the
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kernel, which always stay in memory. Those apps here will more likely be loaded
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in RAM from storage, ran, then discarded so that another userspace program can
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be run.
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That doesn't mean that you can't include that code in your kernel though, but
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you will typically not want to do that.
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2019-06-02 14:05:20 -04:00
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## Userspace convention
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We execute a userspace application by calling the address it's loaded into. This
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means: a userspace application is expected to return.
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Whatever calls the userspace app (usually, it will be the shell), should set
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HL to a pointer to unparsed arguments in string form, null terminated.
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The userspace application is expected to set A on return. 0 means success,
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non-zero means error.
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