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[netCDF #RER-542556]: Real posix I/O in netCDF

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  • Subject: [netCDF #RER-542556]: Real posix I/O in netCDF
  • Date: Tue, 09 Jun 2015 09:57:23 -0600
Hello Liao,

The function you are looking for is `nc_sync()`, in libdispatch/dfile.c.  I 
won't try to duplicate it here, but there is a verbose description of nc_sync() 
and how it is used in the header block of the function.  It actually looks like 
the information is also captured in our user documentation, at 
http://www.unidata.ucar.edu/software/netcdf/docs/group__datasets.html#gaf2d184214ce7a55b0a50514749221245.

In a nutshell, data is synchronized automatically when a netCDF dataset is 
closed, or when you leave `define` mode.  It can also be explicitly synced; I 
recommend reading the full description at the link above, as it is very 
thorough.

I hope this helps!

-Ward

> Dear there,
> 
> I am trying to understand the workflow of netCDF. But I am a
> little confused about when the data is flushed to the disk.
> 
> In other words, when the data is written to the disk? I check
> posixio.c, but it seems that the data is not flushed by the functions
> provided by this file.        Could you tell me the detailed workflow from
> nc_put_var to the data stored in the file on disk.
> 
> Thank you very very much,
> 
> Liao
> 
> Dear there,
> 
> I am trying to understand the workflow of netCDF. But I am a
> little confused about when the data is flushed to the disk.
> 
> In other words, when the data is written to the disk? I check
> posixio.c, but it seems that the data is not flushed by the functions
> provided by this file.        Could you tell me the detailed workflow from
> nc_put_var to the data stored in the file on disk.
> 
> Thank you very very much,
> 
> Liao
> 

Ticket Details
===================
Ticket ID: RER-542556
Department: Support netCDF
Priority: Normal
Status: Closed