---
name: "pmemblk_nblock"
section: "3"
platform: "linux"
package: "libpmemblk-dev"
version: "1.13.1-1.1+b1"
release: "Debian 13 (Trixie)"
platforms: ["linux"]
url: "https://new.carta.tech/pmemblk_bsize"
---

# pmemblk\_nblock(3)

check number of available blocks or usable space in block memory pool

Part of [pmemblk\_bsize(3)](/pmemblk_bsize/3.md).

## NAME

**pmemblk\_bsize**()(DEPRECATED), **pmemblk\_nblock**()(DEPRECATED) - check number of available blocks or usable space in block memory pool

## SYNOPSIS

-

  ```
  #include <libpmemblk.h>
  size_t pmemblk_bsize(PMEMblkpool *pbp);
  size_t pmemblk_nblock(PMEMblkpool *pbp);
  ```

## DESCRIPTION

The **pmemblk\_bsize**() function returns the block size of the specified block memory pool, that is, the value which was passed as *bsize* to **pmemblk\_create**(). *pbp* must be a block memory pool handle as returned by [**pmemblk\_open**(3)](/pmemblk_open/3.md) or [**pmemblk\_create**(3)](/pmemblk_create/3.md).

The **pmemblk\_nblock**() function returns the usable space in the block memory pool. *pbp* must be a block memory pool handle as returned by [**pmemblk\_open**(3)](/pmemblk_open/3.md) or [**pmemblk\_create**(3)](/pmemblk_create/3.md).

## RETURN VALUE

The **pmemblk\_bsize**() function returns the block size of the specified block memory pool.

The **pmemblk\_nblock**() function returns the usable space in the block memory pool, expressed as the number of blocks available.

## SEE ALSO

[**pmemblk\_create**(3)](/pmemblk_create/3.md), [**pmemblk\_open**(3)](/pmemblk_open/3.md), [**libpmemblk**(7)](/libpmemblk/7.md) and **\<https://pmem.io\>**