Aaron-Staples-MacBook-Pro:mongo aaron$ echo 'a' > foo.json
Aaron-Staples-MacBook-Pro:mongo aaron$ ./mongoimport -d d -c c foo.json
connected to: 127.0.0.1
Tue Jan 31 15:39:03 Assertion: 10340:Failure parsing JSON string near: a
0x110439f95 0x11043817b 0x11043839a 0x1103a6cdb 0x10fff5e5a 0x10ffebad7 0x11054871a 0x10ffe3d42 0x10ffe3bb4 
 0   mongoimport                         0x0000000110439f95 _ZN5mongo15printStackTraceERSo + 37
 1   mongoimport                         0x000000011043817b _ZN5mongo11msgassertedEiPKc + 363
 2   mongoimport                         0x000000011043839a _ZNK5mongo13ExceptionInfo6appendERNS_14BSONObjBuilderEPKcS4_ + 0
 3   mongoimport                         0x00000001103a6cdb _ZN5mongo8fromjsonEPKcPi + 411
 4   mongoimport                         0x000000010fff5e5a _ZN6Import8parseRowEPSiRN5mongo7BSONObjERi + 438
 5   mongoimport                         0x000000010ffebad7 _ZN6Import3runEv + 8805
 6   mongoimport                         0x000000011054871a _ZN5mongo4Tool4mainEiPPc + 11592
 7   mongoimport                         0x000000010ffe3d42 main + 66
 8   mongoimport                         0x000000010ffe3bb4 start + 52
Tue Jan 31 15:39:03 exception:BSON representation of supplied JSON is too large: Failure parsing JSON string near: a
Tue Jan 31 15:39:03 
Tue Jan 31 15:39:03 imported 0 objects
Tue Jan 31 15:39:03 ERROR: encountered 1 error