I watched movie : Her (2013). In time 04:44 a song is played and words are as 'When you know you're gonna die'. After end of movie, i read song's name was: When you know you're gonna die by Arcade Fire. I googled and searched in youtube but only got 09 seconds video and mp3. So, i was wondering is there any full length song or not or was it just 09 sec. audio. If anyone knows about this song, please help me. I already searched in imdb and other sites. Youtube link is as: https://www.youtube.com/watch?v=EHDcNEkydSw
As @JohnnyBones says in the comments, the soundtrack for Her was never released officially. Here is the information Wikipedia has on this matter.
The soundtrack has not been released in digital or physical form, and Warner Bros. has not announced any plans to release it in the future. A 13-track score was made available for streaming online in January 2014, before being taken down. During an "Ask Me Anything" (AMA) on Reddit on June 17, 2016, Will Butler mentioned the possibility of a future vinyl release.