I have found a serios of geeky .FLV tutorials and wanted to concatenate them into a single, big, video file. After some research I have come across this oneliner:
$ mencoder -oac copy -ovc copy -o final file1.flv file2.flv file3.flv
-oac and -ovc ask the mencoder to stream copy the files.
-o is used for specifying the output file.
Because mencoder’s flv conversion is a little buggy, you may get an error, like this:
Audio format 0x4134504d is incompatible with '-oac copy', please try '-oac pcm' instead or use '-fafmttag' to override it
Do as they say, replace -oac copy with -oac pcm:
$ mencoder -oac pcm -ovc copy -o final file1.flv file2.flv file3.flv
The mentioned command will make your output file avi, instead of flv, as the first command written in this post. However, this may not bother you.