---
name: "getnetent"
section: "3"
platform: "linux"
package: "man-pages"
version: "6.19-1"
release: "Arch Linux 2026-11-01"
platforms: ["linux", "freebsd", "macos"]
url: "https://new.carta.tech/getnetent"
---

# getnetent(3)

get network entry

## NAME

getnetent, getnetbyname, getnetbyaddr, setnetent, endnetent - get network entry

## LIBRARY

Standard C library (*libc*, *-lc*)

## SYNOPSIS

```
#include <netdb.h>
```

**struct netent \*getnetent(void);**

**struct netent \*getnetbyname(const char \****name***);** **struct netent \*getnetbyaddr(uint32\_t** *net***, int** *type***);**

**void setnetent(int** *stayopen***);** **void endnetent(void);**

## DESCRIPTION

The **getnetent**() function reads the next entry from the networks database and returns a *netent* structure containing the broken-out fields from the entry. A connection is opened to the database if necessary.

The **getnetbyname**() function returns a *netent* structure for the entry from the database that matches the network *name*.

The **getnetbyaddr**() function returns a *netent* structure for the entry from the database that matches the network number *net* of type *type*. The *net* argument must be in host byte order.

The **setnetent**() function opens a connection to the database, and sets the next entry to the first entry. If *stayopen* is nonzero, then the connection to the database will not be closed between calls to one of the **getnet\***() functions.

The **endnetent**() function closes the connection to the database.

The *netent* structure is defined in *\<netdb.h\>* as follows:

```
struct netent {
    char      *n_name;     /* official network name */
    char     **n_aliases;  /* alias list */
    int        n_addrtype; /* net address type */
    uint32_t   n_net;      /* network number */
}
```

The members of the *netent* structure are:

- *n\_name*

  The official name of the network.

- *n\_aliases*

  A NULL-terminated list of alternative names for the network.

- *n\_addrtype*

  The type of the network number; always **AF\_INET**.

- *n\_net*

  The network number in host byte order.

## RETURN VALUE

The **getnetent**(), **getnetbyname**(), and **getnetbyaddr**() functions return a pointer to a statically allocated *netent* structure, or a null pointer if an error occurs or the end of the file is reached.

## FILES

- */etc/networks*

  networks database file

## ATTRIBUTES

For an explanation of the terms used in this section, see [**attributes**(7)](/attributes/7.md).

| | | |
| --- | --- | --- |
| **Interface** | **Attribute** | **Value** |
| **getnetent**() | Thread safety | MT-Unsafe race:netent race:netentbuf env locale |
| **getnetbyname**() | Thread safety | MT-Unsafe race:netbyname env locale |
| **getnetbyaddr**() | Thread safety | MT-Unsafe race:netbyaddr locale |
| **setnetent**(), **endnetent**() | Thread safety | MT-Unsafe race:netent env locale |

In the above table, *netent* in *race:netent* signifies that if any of the functions **setnetent**(), **getnetent**(), or **endnetent**() are used in parallel in different threads of a program, then data races could occur.

## STANDARDS

POSIX.1-2008.

## HISTORY

POSIX.1-2001, 4.3BSD.

Before glibc 2.2, the *net* argument of **getnetbyaddr**() was of type *long*.

## SEE ALSO

[**getnetent\_r**(3)](/getnetent_r/3.md), [**getprotoent**(3)](/getprotoent/3.md), [**getservent**(3)](/getservent/3.md)\
 RFC 1101