---
name: "Mat_VarAddStructField"
section: "3"
platform: "linux"
package: "libmatio"
version: "1.5.30-1"
release: "Arch Linux 2026-11-01"
platforms: ["linux"]
url: "https://new.carta.tech/Mat_VarAddStructField"
---

# Mat\_VarAddStructField(3)

Adds a field to a structure array.

## NAME

**Mat\_VarAddStructField** – Adds a field to a structure array.

## SYNOPSIS

**#include \<matio.h\>**

*int*\

**Mat\_VarAddStructField**(*matvar\_t \*matvar*, *const char \*fieldname*);

## DESCRIPTION

The **Mat\_VarAddStructField**() function adds a fieldname to the structure variable *matvar.*

## RETURN VALUES

0 is returned on success.

## SEE ALSO

[Mat\_VarCreateStruct(3)](/Mat_VarCreateStruct/3.md)