---
name: "sdrtable"
section: "3"
platform: "linux"
package: "ion-doc"
version: "3.2.1+dfsg-1.1"
release: "Debian 9 (Stretch)"
platforms: ["linux"]
url: "https://new.carta.tech/sdrtable"
---

# sdrtable(3)

Simple Data Recorder table management functions

## NAME

sdrtable - Simple Data Recorder table management functions

## SYNOPSIS

```
    #include "sdr.h"
    Object  sdr_table_create        (Sdr sdr, int rowSize, int rowCount);
    int     sdr_table_user_data_set (Sdr sdr, Object table, Address userData);
    Address sdr_table_user_data     (Sdr sdr, Object table);
    int     sdr_table_dimensions    (Sdr sdr, Object table, int *rowSize,
                                        int *rowCount);
    int     sdr_table_stage         (Sdr sdr, Object table);
    Address sdr_table_row           (Sdr sdr, Object table,
                                        unsigned int rowNbr);
    int     sdr_table_destroy       (Sdr sdr, Object table);
```

## DESCRIPTION

The SDR table functions manage table objects in the SDR.  An SDR table comprises N rows of M bytes each, plus optionally one word of user data (which is nominally the address of some other object in the SDR's heap space).  When a table is created, the number of rows in the table and the length of each row are specified; they remain fixed for the life of the table.  The table functions merely maintain information about the table structure and its location in the SDR and calculate row addresses; other SDR functions such as *sdr\_read()* and *sdr\_write()* are used to read and write the contents of the table's rows.  In particular, the format of the rows of a table is left entirely up to the user.

- Object sdr\_table\_create(Sdr sdr, int rowSize, int rowCount)

  Creates a "self-delimited table", comprising *rowCount* rows of *rowSize* bytes each, in the heap space of the indicated SDR.  Note that the content of the table, a two-dimensional array, is a single SDR heap space object of size (*rowCount* x *rowSize*).  Returns the address of the new table on success, zero on any error.

- void sdr\_table\_user\_data\_set(Sdr sdr, Object table, Address userData)

  Sets the "user data" word of *table* to *userData*.  Note that *userData* is nominally an Address but can in fact be any value that occupies a single word.  It is typically used to point to an SDR object that somehow characterizes the table as a whole, such as an SDR string containing a name.

- Address sdr\_table\_user\_data(Sdr sdr, Object table)

  Returns the value of the "user data" word of *table*, or zero on any error.

- void sdr\_table\_dimensions(Sdr sdr, Object table, int \*rowSize, int \*rowCount)

  Reports on the row size and row count of the indicated table, as specified when the table was created.

- void sdr\_table\_stage(Sdr sdr, Object table)

  Stages *table* so that the array it encapsulates may be updated; see the discussion of *sdr\_stage()* in [*sdr*(3)](/sdr/3.md).  The effect of this function is the same as:

  ```
     sdr_stage(sdr, NULL, (Object) sdr_table_row(sdr, table, 0), 0)
  ```

- Address sdr\_table\_row(Sdr sdr, Object table, unsigned int rowNbr)

  Returns the address of the *rowNbr*th row of *table*, for use in reading or writing the content of this row; returns -1 on any error.

- void sdr\_table\_destroy(Sdr sdr, Object table)

  Destroys *table*, releasing all bytes of all rows and destroying the table structure itself.  DO NOT use *sdr\_free()* to destroy a table, as this would leave the table's content allocated yet unreferenced.

## SEE ALSO

[*sdr*(3)](/sdr/3.md), [*sdrlist*(3)](/sdrlist/3.md), [*sdrstring*(3)](/sdrstring/3.md)