1h5jam(1)                    General Commands Manual                   h5jam(1)
2
3
4

NAME

6       h5jam - Add a user block to a HDF5 file
7

SYNOPSIS

9       h5jam -u user_block -i in_file.h5 [-o out_file.h5] [--clobber]
10

DESCRIPTION

12       h5jam concatenates a user_block file and an HDF5 file to create an HDF5
13       file with a user block. The user block can be either  binary  or  text.
14       The  output  file is padded so that the HDF5 header begins on byte 512,
15       1024, etc.. (See the HDF5 File Format.)
16
17       If out_file.h5 is given, a new file is created with the user_block fol‐
18       lowed  by  the  contents  of  in_file.h5.   In  this case, infile.h5 is
19       unchanged.
20
21       If out_file.h5 is not specified, the user_block is added to in_file.h5.
22
23       If in_file.h5 already has a user block, the contents of user_block will
24       be added to the end of the existing user block, and the file shifted to
25       the next boundary. If --clobber is set, any existing user block will be
26       overwritten.
27

EXAMPLE USAGE

29       Create  new  file,  newfile.h5, with the text in file mytext.txt as the
30       user block for the HDF5 file file.h5.
31
32            h5jam -u mytext.txt -i file.h5 -o newfile.h5
33
34       Add text in file mytext.txt to front of HDF5 dataset, file.h5.
35
36            h5jam -u mytext.txt -i file.h5
37
38       Overwrite the user block (if any)  in  file.h5  with  the  contents  of
39       mytext.txt.
40
41            h5jam -u mytext.txt -i file.h5 --clobber
42

RETURN VALUE

44       h5jam returns the size of the output file, or -1 if an error occurs.
45

CAVEATS

47       This tool copies all the data (sequentially) in the file(s) to new off‐
48       sets. For a large file, this copy will take a long time.
49
50       The most efficient way to create a user block is  to  create  the  file
51       with  a  user  block  (see H5Pset_user_block), and write the user block
52       data into that space from a program.
53
54       The user block is completely opaque to the  HDF5  library  and  to  the
55       h5jam and h5unjam tools.  The user block is simply read or written as a
56       string of bytes, which could be text or any kind of binary data.  It is
57       up  to  the  user to know what the contents of the user block means and
58       how to process it.
59
60       When the user block is extracted, all the data is written to  the  out‐
61       put, including any padding or unwritten data.
62
63       This  tool  moves  the HDF5 file through byte copies, i.e., it does not
64       read or interpret the HDF5 objects.
65

SEE ALSO

67       h5dump(1),  h5ls(1),  h5diff(1),  h5import(1),  gif2h5(1),   h52gif(1),
68       h5perf(1), h5unjam(1).
69
70
71
72                                                                      h5jam(1)
Impressum