file descriptor

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file descriptor

(programming, operating system)
An integer that identifies an open file within a process. This number is obtained as a result of opening a file. Operations which read, write, or close a file would take the file descriptor as an input parameter.

In many operating system implementations, file descriptors are small integers which index a table of open files. In Unix, file descriptors 0, 1 and 2 correspond to the standard input, standard output and standard error files respectively.

See file descriptor leak.
This article is provided by FOLDOC - Free Online Dictionary of Computing (

file handle

A temporary reference (typically a number) assigned by the operating system to a file that an application has asked it to open. The handle is used throughout the session to access the file. In the Unix/Linux world, a file handle is called a "file descriptor."
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References in periodicals archive ?
This XML file descriptor asks the engine to invoke the advice "authentication" before invocation of any method whose signature matches the regular expression "WithD*".
There are four different types of uses for fixed-size blocks in this data structure: user data, directory entries, file descriptors, and indirect pointers.
That is, an IOL_read operation yields data that either reflect all or none of the changes resulting :from a concurrent IOL_write operation on the same file descriptor. The data returned by an IOL_read are effectively a "snapshot" of the data contained in the object associated with the file descriptor.