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puffs_flush(3) [netbsd man page]

PUFFS_FLUSH(3)						   BSD Library Functions Manual 					    PUFFS_FLUSH(3)

puffs_flush -- puffs kernel cache flushing and invalidation routines LIBRARY
puffs Convenience Library (libpuffs, -lpuffs) SYNOPSIS
#include <puffs.h> int puffs_inval_namecache_dir(struct puffs_usermount *pu, puffs_cookie_t cookie); int puffs_inval_namecache_all(struct puffs_usermount *pu); int puffs_inval_pagecache_node(struct puffs_usermount *pu, puffs_cookie_t cookie); int puffs_inval_pagecache_node_range(struct puffs_usermount *pu, puffs_cookie_t cookie, off_t start, off_t end); int puffs_flush_pagecache_node(struct puffs_usermount *pu, puffs_cookie_t cookie); int puffs_flush_pagecache_node_range(struct puffs_usermount *pu, puffs_cookie_t cookie, off_t start, off_t end); DESCRIPTION
These routines are used inform the kernel that any information it might have cached is no longer valid. puffs_inval_namecache_dir() invali- dates the name cache for a given directory. The argument cookie should describe an existing and valid directory cookie for the file system. Similarly, puffs_inval_namecache_all() invalidates the name cache for the entire file system (this routine might go away). The cached pages (file contents) for a regular file described by cookie are invalidated using puffs_inval_pagecache_node(). A specific range can be invalidated using puffs_inval_pagecache_node_range() for a platform specific page level granularity. The offset start will be truncated to a page boundary while end will be rounded up to the next page boundary. As a special case, specifying 0 as end will invalidate all contents from start to the end of the file. It is especially important to note that these routines will not only invalidate data in the "read cache", but also data in the "write back" cache (conceptually speaking; in reality they are the same cache), which has not yet been flushed to the file server. Therefore any unflushed data will be lost. The counterparts of the invalidation routines are the flushing routines puffs_flush_pagecache_node() and puffs_flush_pagecache_node_range(), which force unwritten data from the kernel page cache to be written. For the flush range version, the same range rules as with the invalida- tion routine apply. The data is flushed asynchronously, i.e. if the routine returns successfully, all the caller knows is that the data has been queued for writing. SEE ALSO
puffs(3) BSD
April 7, 2007 BSD

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XGetEventData(3)						  XLIB FUNCTIONS						  XGetEventData(3)

XGetEventData, XFreeEventData, XGenericEventCookie - retrieve and free additional event data through cookies. SYNTAX
Bool XGetEventData(Display *display, XGenericEventCookie *cookie); void XFreeEventData(Display *display, XGenericEventCookie *cookie); ARGUMENTS
display Specifies the connection to the X server. cookie Specifies the cookie to free or retrieve the data for. STRUCTURES
typedef struct { int type; unsigned long serial; Bool send_event; Display *display; int extension; int evtype; unsigned int cookie; void *data; } XGenericEventCookie; DESCRIPTION
Some extension XGenericEvents require additional memory to store information. For these events, the library returns a XGenericEventCookie with a token ('cookie') unique to this event. The XGenericEventCookie's data pointer is undefined until XGetEventData is called. The XGetEventData function retrieves this extra data for the given cookie. No round-trip to the server is required. If the cookie is invalid or the event is not an event handled by cookie handlers, False is returned. If XGetEventData returns True, the cookie's data pointer points to the memory containing the event information. A client must call XFreeEventData to free this memory. XGetEventData returns False for multiple calls for the same event cookie. The XFreeEventData function frees the data associated with a cookie. A client must call XFreeEventData for each cookie claimed with XGetEventData. EXAMPLE CODE
XEvent event; XGenericEventCookie *cookie = &ev; XNextEvent(display, &event); if (XGetEventData(display, cookie)) { handle_cookie_event(cookie->data); } else handle_event(&event); } XFreeEventData(display, cookie); NOTES
A cookie is defined as unclaimed if it has been returned to the client through XNextEvent but its data has not been retrieved via XGetEventData. Subsequent calls to XNextEvent may free memory associated with unclaimed cookies. Multi-threaded X clients must ensure that XGetEventData is called before the next call to XNextEvent. SEE ALSO
XNextEvent(3), Xlib - C Language X Interface X Version 11 libX11 1.5.0 XGetEventData(3)
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