---
name: "rpma_log_set_function"
section: "3"
platform: "linux"
package: "librpma-dev"
version: "1.3.0-2+b3"
release: "Debian 13 (Trixie)"
platforms: ["linux"]
url: "https://new.carta.tech/rpma_log_set_function"
---

# rpma\_log\_set\_function(3)

set the logging function

## NAME

**rpma\_log\_set\_function** - set the logging function

## SYNOPSIS

```
      #include <librpma.h>
      typedef void rpma_log_function(
              enum rpma_log_level level,
              const char *file_name,
              const int line_no,
              const char *function_name,
              const char *message_format,
              ...);
      int rpma_log_set_function(rpma_log_function *log_function);
```

## DESCRIPTION

**rpma\_log\_set\_function**() allows choosing the function which will get all the generated logging messages. The *log\_function* can be either RPMA\_LOG\_USE\_DEFAULT\_FUNCTION which will use the default logging function (built into the library) or a pointer to a user-defined function.

Parameters of a user-defined log function are as follow:

- •

  *level* - the log *level* of the message

- •

  *file\_name* - name of the source file where the message coming from. It could be set to NULL and in such case neither *line\_no* nor *function\_name* are provided.

- •

  *line\_no* - the source file line where the message coming from

- •

  *function\_name* - the function name where the message coming from

- •

  *message\_format* - [**printf**(3)](/printf/3.md)**-like** format string of the message

- •

  "..." - additional arguments of the message format string

## THE DEFAULT LOGGING FUNCTION

The initial value of the logging function is RPMA\_LOG\_USE\_DEFAULT\_FUNCTION. This function writes messages to [**syslog**(3)](/syslog/3.md) (the primary destination) and to [**stderr**(3)](/stderr/3.md) (the secondary destination).

## RETURN VALUE

**rpma\_log\_set\_function**() function returns 0 on success or error code on failure.

## ERRORS

- •

  RPMA\_E\_AGAIN - a temporary error occurred, the retry may fix the problem

## NOTE

The logging messages on the levels above the RPMA\_LOG\_THRESHOLD *level* won't trigger the logging function.

The user defined function must be thread-safe.

## SEE ALSO

[**rpma\_log\_get\_threshold**(3)](/rpma_log_get_threshold/3.md), [**rpma\_log\_set\_threshold**(3)](/rpma_log_set_threshold/3.md), [**librpma**(7)](/librpma/7.md) and https://pmem.io/rpma/