Rafael Garcia-Suarez <email@example.com>: > setbuf/setvbuf aren't available with a PerlIO-enabled perl. Thanks. Here's my problem. I want two processes to access the same (small) file concurrently. Process A reads part of the file. Process B modifies part of the file. Then process A wants to see the change. But it can't, because the block it just read is buffered, and subsequent reads are all coming from the buffer, which records the state of the file before the change, instead of from the real file. I thought my choices were a) use setvbuf() to discard the buffer, perhaps temporarily, or b) discard the buffered I/O system entirely and rewrite everything in terms of sysread(), effectively reimplementing the entire buffered I/O subsystem in Perl. But now it appears that my only choice is (b). This isn't very attractive. Is there some other option I've overlooked?