Access to Files


A "file descriptor" is a small integer number
open(2), pipe(2), socket(2) create fds
dup(2) and fork(2) clone them
close(2) and exit(2) close them
read(2), write(2), recvfrom(2), ... 
lseek(2), llseek(2) to move within the file
access(2), stat(2), fstat(2) to get information
errors are reported in the global variable errno

Information on open files
"fuser" command
"netstat -ap" command
directory /proc/<pid>/fd