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Test Your Knowledge in Computers #576
Difficulty: Medium
All programming languages have automatic garbage collection that monitors the dynamically allocated pieces of memory and determine if any variable in the program still references it. If the memory is no longer referenced, it is 'garbage' and becomes eligible to be 'collected'.
True or False?
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stderr(4) [bsd man page]

FD(4)							     Kernel Interfaces Manual							     FD(4)

NAME
fd, stdin, stdout, stderr file descriptor files DESCRIPTION
The files /dev/fd/0 through /dev/fd/# refer to file descriptors which can be accessed through the file system. If the file descriptor is open and the mode the file is being opened with is a subset of the mode of the existing descriptor, the call: fd = open("/dev/fd/0", mode); and the call: fd = fcntl(0, F_DUPFD, 0); are equivalent. Opening the files /dev/stdin, /dev/stdout and /dev/stderr is equivalent to the following calls: fd = fcntl(STDIN_FILENO, F_DUPFD, 0); fd = fcntl(STDOUT_FILENO, F_DUPFD, 0); fd = fcntl(STDERR_FILENO, F_DUPFD, 0); Flags to the open(2) call other than O_RDONLY, O_WRONLY and O_RDWR are ignored. FILES
/dev/fd/# /dev/stdin /dev/stdout /dev/stderr SEE ALSO
tty(4) 4th Berkeley Distribution February 4, 1997 FD(4)

Check Out this Related Man Page

FD(4)							   BSD Kernel Interfaces Manual 						     FD(4)

NAME
fd, stdin, stdout, stderr -- file descriptor files DESCRIPTION
The files /dev/fd/0 through /dev/fd/# refer to file descriptors which can be accessed through the file system. If the file descriptor is open and the mode the file is being opened with is a subset of the mode of the existing descriptor, the call: fd = open("/dev/fd/0", mode); and the call: fd = fcntl(0, F_DUPFD, 0); are equivalent. Opening the files /dev/stdin, /dev/stdout and /dev/stderr is equivalent to the following calls: fd = fcntl(STDIN_FILENO, F_DUPFD, 0); fd = fcntl(STDOUT_FILENO, F_DUPFD, 0); fd = fcntl(STDERR_FILENO, F_DUPFD, 0); Flags to the open(2) call other than O_RDONLY, O_WRONLY and O_RDWR are ignored. IMPLEMENTATION NOTES
By default, /dev/fd is provided by devfs(5), which provides nodes for the first three file descriptors. Some sites may require nodes for additional file descriptors; these can be made available by mounting fdescfs(5) on /dev/fd. FILES
/dev/fd/# /dev/stdin /dev/stdout /dev/stderr SEE ALSO
tty(4), devfs(5), fdescfs(5) BSD
June 9, 1993 BSD

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