gai_error - Linux


gai_error is a tool for looking up and interpreting error codes returned by the GNU C Library’s getaddrinfo() and getnameinfo() functions. These functions are used to resolve hostnames to IP addresses and vice versa, and they can return a variety of error codes. gai_error provides a human-readable description of each error code, as well as a list of possible causes.


gai_error [OPTION]... [ERROR-CODE]...


  • -h, –help: Display a help message and exit.
  • -v, –version: Display the version of gai_error and exit.


To look up the meaning of a single error code, such as EAI_NONAME:

$ gai_error EAI_NONAME
EAI_NONAME: Name or service not known

To look up multiple error codes at once:


To look up all possible error codes:

$ gai_error

Common Issues

One common issue when using gai_error is that it may not recognize all possible error codes. This can happen if you are using a version of the GNU C Library that is older than the version of gai_error that you are using. To resolve this issue, update your version of the GNU C Library or use an older version of gai_error.


gai_error can be integrated with other Linux commands using pipes. For example, the following command will look up the meaning of the error code returned by the ping command:

$ ping -c 1 | grep 'connect: Network is unreachable' | cut -d: -f3 | gai_error
Connect request failed - Network unreachable

Related Commands

  • getaddrinfo
  • getnameinfo