>Unfortunately, the open fails unless there is somebody reading from >the fifo- It is possible to open a fifo for read without blocking, but >I couldn't find any way to do this for writing. For reading, it also >seems to be possible to ge a signal if data is available, but I can't >think of any way to get such a signal if the pipe is opened for >reading (so I could afterwards open it for writing). >
Hello, >From the perlipc.pod, A fifo is convenient when you want to connect a process to an unrelated one. When you open a fifo, the program will block until there's something on the other end. For example, let's say you'd like to have your .signature file be a named pipe that has a Perl program on the other end. Now every time any program (like a mailer, news reader, finger program, etc.) tries to read from that file, the reading program will block and your program will supply the new signature. We'll use the pipe-checking file test -p to find out whether anyone (or anything) has accidentally removed our fifo. So I think there is no way but you just need to keep another program to be reading from the FIFO when you're writing to it. -- Books below translated by me to Chinese. Practical mod_perl: http://home.earthlink.net/~pangj/mod_perl/ Squid the Definitive Guide: http://home.earthlink.net/~pangj/squid/ -- To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED] <http://learn.perl.org/> <http://learn.perl.org/first-response>
