HI_Earliest

Cogent API and Utilities: Version 4.1
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# `HI_Earliest`

`HI_Earliest` -- gives the earliest value in a history.

## Syntax

    #include <cogent/cogent.h>

``ST_STATUS HI_Earliest`(IP_hTASK historian, char* retbuf, int buflen, char* histname, HI_stVALUE* data);`

## Arguments

`historian`

  The task pointer to the Cascade Historian program.

`retbuf`

  An optional buffer containing an error message.

`buflen`

  The length in bytes of `retbuf`. If `retbuf` is non-NULL, this must be a valid non-zero length. If `retbuf` is NULL, this parameter is ignored.

`histname`

  The name of a history.

`data`

  The value and time of the first data item in the history.

## Returns

`ST_OK` on success. Otherwise `ST_ERROR`, and the `retbuf` will contain a NULL-terminated character string with an error message. If the return value is `ST_OK`, the `retbuf` may not contain useful information.

## Description

This function returns the value for the first data item in the history. This item may be either in a file or in memory.

This function corresponds to the Cascade Historian earliest command and the `hist_earliest` dynamic library function.

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