Prevent writing to a deleted file
Prevent writing to a deleted file

When a dataFile is deleted, the f file pointer is set to nil.  Since deleting
a file happens asynchronously, code that had a reference when it was valid may
run when it's gone.

mvadu/influxdb,mnuessler/influxdb,mark-rushakoff/influxdb,Mindera/influxdb,joaopedrotaveira/influxdb,jgeiger/influxdb,jgeiger/influxdb,arussellsaw/influxdb,samaitra/influxdb,arussellsaw/influxdb,arussellsaw/influxdb,archsaber/influxdb,jonseymour/influxdb,linearb/influxdb,n1tr0g/influxdb,arussellsaw/influxdb,pkittenis/influxdb,CVTJNII/influxdb-tjnii,arussellsaw/influxdb,jonseymour/influxdb,jipperinbham/influxdb,lgpeterson/influxdb,otoolep/influxdb,mvadu/influxdb,CVTJNII/influxdb-tjnii,samaitra/influxdb,jipperinbham/influxdb,jgeiger/influxdb,chenziliang/influxdb,daachi/influxdb,m4ce/influxdb,pkittenis/influxdb,influxdata/influxdb,influxdata/influxdb,nickrobinson/influxdb,apigee/influxdb,pkittenis/influxdb,li-ang/influxdb,mark-rushakoff/influxdb,otoolep/influxdb,m4ce/influxdb,CVTJNII/influxdb-tjnii,runner-mei/influxdb,influxdb/influxdb,li-ang/influxdb,mvadu/influxdb,influxdb/influxdb,jipperinbham/influxdb,linearb/influxdb,linearb/influxdb,jipperinbham/influxdb,lgpeterson/influxdb,m4ce/influxdb,daachi/influxdb,sudabon/influxdb,apigee/influxdb,archsaber/influxdb,jonseymour/influxdb,m4ce/influxdb,jonseymour/influxdb,pablolmiranda/influxdb,nickrobinson/influxdb,benbjohnson/influxdb,vladlopes/influxdb,jipperinbham/influxdb,joaopedrotaveira/influxdb,jonseymour/influxdb,sudabon/influxdb,pablolmiranda/influxdb,pablolmiranda/influxdb,archsaber/influxdb,apigee/influxdb,Mindera/influxdb,otoolep/influxdb,apigee/influxdb,linearb/influxdb,vladlopes/influxdb,pkittenis/influxdb,otoolep/influxdb,mark-rushakoff/influxdb,Mindera/influxdb,sudabon/influxdb,nooproblem/influxdb,mnuessler/influxdb,nickrobinson/influxdb,mvadu/influxdb,mark-rushakoff/influxdb,n1tr0g/influxdb,jonseymour/influxdb,daachi/influxdb,samaitra/influxdb,otoolep/influxdb,m4ce/influxdb,sudabon/influxdb,jgeiger/influxdb,Mindera/influxdb,benbjohnson/influxdb,nickrobinson/influxdb,nooproblem/influxdb,m4ce/influxdb,samaitra/influxdb,otoolep/influxdb,pkittenis/influxdb,samaitra/influxdb,chenziliang/influxdb,samaitra/influxdb,mark-rushakoff/influxdb,jgeiger/influxdb,jipperinbham/influxdb,sudabon/influxdb,joaopedrotaveira/influxdb,mnuessler/influxdb,pkittenis/influxdb,daachi/influxdb,n1tr0g/influxdb,mark-rushakoff/influxdb,vladlopes/influxdb,runner-mei/influxdb,Mindera/influxdb,mnuessler/influxdb,nooproblem/influxdb,runner-mei/influxdb,chenziliang/influxdb,sudabon/influxdb,linearb/influxdb,CVTJNII/influxdb-tjnii,n1tr0g/influxdb,chenziliang/influxdb,CVTJNII/influxdb-tjnii,nickrobinson/influxdb,apigee/influxdb,pablolmiranda/influxdb,runner-mei/influxdb,nooproblem/influxdb,n1tr0g/influxdb,vladlopes/influxdb,mnuessler/influxdb,influxdb/influxdb,archsaber/influxdb,nooproblem/influxdb,n1tr0g/influxdb,Mindera/influxdb,lgpeterson/influxdb,jgeiger/influxdb,influxdb/influxdb,benbjohnson/influxdb,mnuessler/influxdb,influxdb/influxdb,mvadu/influxdb,joaopedrotaveira/influxdb,lgpeterson/influxdb,daachi/influxdb,lgpeterson/influxdb,influxdb/influxdb,apigee/influxdb,CVTJNII/influxdb-tjnii,benbjohnson/influxdb,daachi/influxdb,joaopedrotaveira/influxdb,mvadu/influxdb,pablolmiranda/influxdb,arussellsaw/influxdb