This program is in the public domain.
Continuing my pursuit of minimalist software, I bring you the ultimately trivial 'wavelength'. Wavelength will attempt to open a wave file, and upon determining that the header is somewhat in good order, overwrite the data length entry in the header with the actual data length found to be in the file. This may or may not match the number that is found in the header, and so wavelength will perform no meaningful operation on a correctly formatted wave file. It is intended to be used to fix files that report the length wrong in the header.
I made this utility because I like to use command line record programs. The problem is that one doesn't always know how long she will be recording, and so the programs will just continue recording until a ctrl-C. This causes the program to be unable to update the header with the amount of data recorded so far.
I could alter one of these programs to trap the break signal and update the header on exit, but this does not fix the case of recording to stdout, and piping through other utilities such as say, a command line vu meter. The record program cannot seek on the pipe and so the resultant file at the end of the pipe must remain broken.
I have altered my record program to exit with zero status on ctrl-C, and so I can put it in a script like so:
record | vu > my_new.wav
wavelength my_new.wav
Then I can record to my heart's content, press ctrl-C, and the script will stop recording and proceed to the fixing of the header. Now other applications can read the file without failing or complaining.
Toby Shepard
toby@rcsreg.com