---
name: "ibm_hosts"
section: "5"
platform: "linux"
package: "3270-common"
version: "4.3ga10-5"
release: "Debian 13 (Trixie)"
platforms: ["linux"]
url: "https://new.carta.tech/ibm_hosts"
---

# ibm\_hosts(5)

host database for x3270 and c3270

## NAME

ibm\_hosts - host database for x3270 and c3270

## SYNOPSIS

/usr/lib/X11/x3270/ibm\_hosts

## DESCRIPTION

The **ibm\_hosts** file contains information regarding IBM hosts on the network. An *IBM host* is a host which can communicate with a 3270 terminal emulator such as **x3270** or **c3270**. Each line defines a name in the following format (optional fields are shown in brackets):

*name*	*type* \[*opt*:\]...\[*luname*@\]*hostname*\[:*port*\] \[*actions*\]

Items are separated by any number of blanks and/or TAB characters. A line beginning with # is taken as a comment (note that # anywhere else on a line does *not* indicate a comment).

The *name* field is a mnemonic used to identify the host.

The *type* field is a keyword that indicates the type of entry. The value **primary** means that the *name* will be included in host-selection menus that may be displayed by a 3270 emulator. The value **alias** means that the *name* will not be included in menus, but will still be accepted as valid input when a host name is required.

The *hostname* field is the Internet hostname or dot-notation Internet address of the host.

The *hostname* can include \`s:' or \`p:' prefixes, e.g., **s:finicky** (see the [*x3270*(1)](/x3270/1.md) or [*c3270*(1)](/c3270/1.md) man page sfor details). It can also include an LU name, separated by an \`@' character, e.g., **oddlu@bluehost**. Finally, it can include a non-default *port* number, appended to the *hostname* with a colon \`:' character, e.g., **bluehost:97**. (For compatibility with earlier versions of *x3270*, the *port* can also be separated by a slash \`/' character.)

The optional *actions* field specifies actions to be taken once the connection is made and a data-entry field is defined. If the text looks like an action, e.g., **PF(1)**, it is unmodified; otherwise it is taken as the parameter to the **String()** action. The *actions* are not intended for entering usernames and passwords; rather they provide an automated way of specifying a front-end menu option.

## EXAMPLE

Given the following **ibm\_hosts** file:

mvs	primary	mvs-host\
 tso	alias	mvs-host\
 mvs2	primary	mvs-host:4012\
 vm	primary	vtam	Tab() [String(3)](/String/3.md) Enter()

A 3270 emulator will display four names (**mvs**, **mvs2**, **afhost** and **vm**) on its hosts menu. The names **mvs** and **tso** will cause connections to the host **mvs-host**. The name **mvs2** will also cause a connection to **mvs-host**, but to port 4012 rather than the emulator's default port (usually 23). The name **vm** will cause the 3270 emulator to connect to the host **vtam** (presumably some sort of host-selection front-end), enter the string \`3' on the second data-entry field on the screen, and send the Enter AID sequence.

## FILES

/usr/lib/X11/x3270/ibm\_hosts

## SEE ALSO

[x3270(1)](/x3270/1.md), [c3270(1)](/c3270/1.md)