---
name: "hdfpack"
section: "1"
platform: "linux"
package: "hdf4-tools"
version: "4.3.0-1+b1"
release: "Debian 13 (Trixie)"
platforms: ["linux"]
url: "https://new.carta.tech/hdfpack"
---

# hdfpack(1)

compress an HDF file

## NAME

hdfpack - compress an HDF file

## SYNOPSIS

**hdfpack** \[**-i**\|**-b**\] \[**-d** *data-descriptors-per-block*\] \[**-t** *linked-blocks-per-table-entry*\] *input-hdf-file* *output-hdf-file*

## DESCRIPTION

**hdfpack** compresses all of the data in an HDF file and writes the compressed data to a second HDF file.

## OPTIONS

- **-b**

  Non-coalesced Blocks.  **hdfpack** will not coalesce linked-block elements.

- **-i**

  Interactive Mode.  **hdfpack** will prompt for each linked-block element.

- **-d** *num*

  Write an output file with the specified number of data descriptors per block of data descriptors.

- **-t** *num*

  Write an output file with the specified number of linked blocks per table entry.

## EXAMPLES

To compress the data in the file named "aa.hdf" and store the compressed data in the file named "aa.cmp", use the following hdfpack command:

```
        hdfpack aa.hdf aa.cmp
```

Suppose a file named "bb.hdf" contains data elements stored as sequences of linked blocks. The following hdfpack command compresses the file while leaving the linked-block elements intact, and writes the compressed data to a file named "bb.blk".

```
        hdfpack -b bb.hdf bb.blk
```

## SEE ALSO

[**hdfcomp**(1)](/hdfcomp/1.md), [**hdf**(5)](/hdf/5.md)