DH_AppendString

Cogent API and Utilities: Version 4.1
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# `DH_AppendString`

`DH_AppendString` -- appends a string to a point.

## Syntax

    #include <cogdb.h>

``ST_STATUS DH_AppendString`(IP_Task* myself, PT_pCPOINT ppoint, char* str, IP_Msg* hmsg, ER_hLIST elist);`

## Arguments

`myself`

  The task handle associated with this task. This should always be the return value from `IP_NserveInit`.

`ppoint`

  A pointer to a Cascade DataHub point structure. All fields are valid, and will be treated by the write, but in the first call on a point the address field must be zero. It will be filled in automatically. This address will be valid so long as the point exists in the datahub, and if, in subsequent `DH_*` functions, the address is provided for this point, the function will run slightly faster.

`str`

  The string of characters to be appended to the existing point value.

`hmsg`

  A handle to a previously allocated message structure (using IP_MsgCreate) providing enough buffer space to handle the inter-process communication associated with the datahub transaction.

`elist`

  A return value containing error information. This is unimplemented in this version, and should be `NULL`.

## Returns

`ST_OK` on success, `ST_ERROR` on failure, or some other value of `ST_STATUS`.

## Description

This function appends a string to the value of a point. It is an atomic function that operates in one step, without reading or evaluating the existing value of the point. This provides a way to modify the value quickly, without interference or serialization problems.

## See Also

DH_PointAdd

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