salutations, 

syscalltrack's log device file is a character device. Reading from it
with cat(1) works fine, but reading from it with tail(1) produces no
output. 

At first we thought that it was a bug with our handling of read() and
(lack of) handling of lseek(), but it appears that 'tail /dev/urandom'
bechaves in exactly the same way. 

Perusing the tail source code shows that for files which are not
regular files, tail just hordes up all output, until it runs out of
memory or EOF is reached and only then it prints it. Does anyone know
why it behaves this way for character device files and pipes? 

Thanks, 
Muli. 
-- 
Muli Ben-Yehuda
syscalltrack hacker-at-large

Attachment: msg21693/pgp00000.pgp
Description: PGP signature

Reply via email to