January 28, 2008 PUFFS_CC 3

### NAME

puffs_cc - puffs continuation routines

### LIBRARY

### SYNOPSIS

```void` puffs_cc_yield(```struct puffs_cc *pcc`)
```void` puffs_cc_continue(```struct puffs_cc *pcc`)
```void` puffs_cc_schedule(```struct puffs_cc *pcc`)
```struct` `puffs_cc``*` puffs_cc_getcc(```struct puffs_usermount *pu`)

### DESCRIPTION

These routines are used for the cooperative multitasking suite present in puffs.

puffs_cc_yield(```pcc`)
  Suspend and save the current execution context and return control to the previous point. In practice, from the file system author perspective, control returns back to where either the mainloop or where puffs_dispatch_exec(``) was called from.

puffs_cc_continue(```pcc`)
  Will suspend current execution and return control to where it was before before calling puffs_cc_yield(``). This is rarely called directly but rather through puffs_dispatch_exec(``).

puffs_cc_schedule(```pcc`)
  Schedule a continuation. As opposed to puffs_cc_continue(``) this call returns immediately. ```pcc` will be scheduled sometime in the future.

puffs_cc_getcc(```pu`)
  Returns the current pcc or ```NULL` if this is the main thread. NOTE: The argument pu will most likely disappear at some point.

Before calling puffs_cc_yield(``) a file system will typically want to record some cookie value into its own internal bookkeeping. This cookie should be hooked to the pcc so that the correct continuation can be continued when the event it was waiting for triggers. Alternatively, the puffs_framebuf(3) framework and puffs_mainloop(``) can be used for handling this automatically.

### SEE ALSO

puffs(3), puffs_framebuf(3)