Availability: All operators Short options: ‘-h’ Long options: ‘--hst’, ‘--history’ |
history
global attribute to
any file they create or modify.
The history
attribute consists of a timestamp and the full string
of the invocation command to the operator, e.g., ‘Mon May 26 20:10:24
1997: ncks in.nc foo.nc’.
The full contents of an existing history
attribute are copied
from the first input-file to the output-file.
The timestamps appear in reverse chronological order, with the most
recent timestamp appearing first in the history
attribute.
Since NCO and many other netCDF operators adhere to the
history
convention, the entire data processing path of a given
netCDF file may often be deduced from examination of its history
attribute.
As of May, 2002, NCO is case-insensitive to the spelling
of the history
attribute name.
Thus attributes named History
or HISTORY
(which are
non-standard and not recommended) will be treated as valid history
attributes.
When more than one global attribute fits the case-insensitive search
for "history", the first one found will be used.
history
attribute
To avoid information overkill, all operators have an optional switch
(‘-h’, ‘--hst’, or ‘--history’) to override
automatically appending the history
attribute
(see ncatted netCDF Attribute Editor).
Note that the ‘-h’ switch also turns off writing the
nco_input_file_list
attribute for multi-file operators
(see File List Attributes).