Operations on BibTeX files.
Input is taken from files named on the command line.
 -help        Show this help.
 -entryTypes  List the standard entry types.
 -fieldNames=ETYPE  List the standard fields for ETYPE if given, or all types.
 -otherFieldNames   List the additional fields for -keepCommonFields.
Filtering out entries or fields (LIST is comma-separated):
 -keep=LIST          Keep only entries whose keys are named in LIST.
 -keepTypes=LIST         Keep only entries with types named in LIST.
 -keepByFields=LIST     Keep only entries with fields named in LIST.
 -keepFields=LIST                    Keep only fields named in LIST.
 For each -keepX option, there is a corresponding -discardX option.
 -keepStandardFields  Keep the standard fields for each entry type.
 -keepCommonFields    Keep the standard fields plus some commonly used fields.
Sorting fields within entries:
 -sortCheck   Check that fields are sorted (-msgLevel=Warn shows unsorted).
 -sortFields  Sort fields into the current sort order.
 -sortOrder=LIST  Set the sort order to LIST if given, or list the current one.
Bracing and quoting:
 -braceAll    Convert any quoted fields to braces.
 -quoteAll    Convert any braced fields to quotes.
Keys:
 -keyHelp     Show help describing how keys are calculated.
 -keyCheck    Compare each entry's key, key field, and calculated key.
 -keyCalculate  Give each entry the key calculated for it.
 -keyFieldCalculate  Give each entry a key field calculated for it.
 -keyFromField  Give each entry the key given in its key field.
 -crossrefsFrom=DIR  Get crossreferenced info from DIR (default is current dir).
Field values:
 -addToday=FIELD  Add a field named FIELD whose value is today's date.
              If no field is named, "bibcreated" is assumed, and
              "annotated" is added if an "annotation"  field is present.
 -expandCrossrefs=DIR  Expand cross-references if possible.  Look in DIR
                for crossreferenced entries (default is current directory).
 -standardizeAuthors  Change author names to last, first ordering.
Output options (default is no output):
 -showEntry   Show each entry.
 -single      Write each field on a single line, rather than justified.
 -humanize    Write author/editor names in firstname-lastname order.
 -showFname   Show each entry's file name.
 -showType    Show each entry's type (without the initial @).
 -showKey     Show each entry's key, or prefix entry lines with it..
 -showFieldValues=LIST  Show the values, only, of the listed fields.
 -sortEntries  Show entries sorted by key (rather than in order they were read).
 -toKeyFile=DIR  Write the entry for KEY to a file named DIR/KEY.bib.
                If DIR is not given, default is the current directory.
 -out=FNAME   Write output for all entries to FNAME, or stdout if none given.
 -msg=FNAME   Write warnings to FNAME rather than stderr, or stdout none given.
 -msgLevel=X  Show warnings of various types: =None =Err =Act =Warn =All
 -stats=X     Show statistics: empty or =count (default), =overall, =detailed.