Pipe Verisi Nerede Saklanır

Giriş
Eski Unix'lerde pipe'a giren veri diskte saklanırdı. Günümüzde disk yerine RAM kullanılıyor. Açıklaması şöyle

Early versions of Unix didn't hold pipe data in RAM. They stored them on disc. Pipes had i-nodes; on a disc device that was denoted the pipe device. The system administrator ran a program named /etc/config to specify (amongst other things) which volume on which disc was the pipe device, which volume was the root device, and which the dump device.

The amount of pending data was constrained by the fact that only the direct blocks of the i-node on disc were used for storage. This mechanism made the code simpler, because much the same algorithm was employed for reading from a pipe as was employed for reading for a regular file, with some tweaks caused by the fact that pipes are non-seekable and the buffer is circular.

This mechanism was replaced by others in the middle to late 1980s. SCO XENIX gained the "High Performance Pipe System", which replaced i-nodes with in-core buffers. 4BSD made unnamed pipes into socketpairs. AT&T reimplemented pipes using the STREAMS mechanism.

And of course the sort program performed a limited internal sort of 32KiB chunks of input (or whatever smaller amount of memory it could allocate if 32KiB was not available), writing the sorted results to intermediate stmX?? files in /usr/tmp/ which it then externally merge sorted to provide the final output.

Named Pipe (FIFO) oluşturmak için mkfifo komutu kullanılabilir.