NAME | SYNOPSIS | FEATURES | DESCRIPTION | RESTRICTIONS | RETURN VALUE | ERRORS | ATTRIBUTES | SEE ALSO
#include <mem/chMem.h>int dcIsDirty(KnLcId lcid);
PXM_EXT
This system call is strictly reserved for internal use only. It MUST NOT be used by any application.
The dcIsDirty function returns 0 if the data cache defined by the lcid argument has not been modified through mapping. It returns a non-null value if the data cache defined by the lcid argument has been dirtied through mapping. The data cache dirty bit is set whenever a dirty mapped page is unloaded from mmu tables or is sync'ed. This may happen when a rgnFree nucleus call occurs or when a dcSync or dcFlush call is invoked. After the dirty bit of the data cache has been tested, it is reset. Thus, a subsequent call to dcIsDirty will return a null value. Modification of a data cache through a call to dcWrite will not set the data cache dirty bit.
This call is provided mainly to enable filesytems to determine whether a file has been modified through mapping.
The current implementation is only applicable to trusted supervisor actors.
This function returns 0 if the data cache is not dirty, 1 otherwise.
No error messages are returned.
See attributes(5) for descriptions of the following attributes:
ATTRIBUTE TYPE | ATTRIBUTE VALUE |
---|---|
Interface Stability | Evolving |
dcAlloc(2SEG), dcFlush(2SEG), dcFree(2SEG), dcRead(2SEG), dcWrite(2SEG), dcPgNumber(2SEG), dcCluster(2SEG), dcSync(2SEG), dcPxmDeclare(2SEG), rgnMapFromDtCache(2SEG), rgnInitFromDtCache(2SEG), rgnFlush(2SEG)
NAME | SYNOPSIS | FEATURES | DESCRIPTION | RESTRICTIONS | RETURN VALUE | ERRORS | ATTRIBUTES | SEE ALSO