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Topic: uniform representation of files and sequences
topics >
computer science >
data >
file
Topic:
file input/output
Topic:
I/O streams
Topic:
processing a sequence
Topic:
uniform data model
Topic:
uniform language systems
Topic:
software tools
Topic:
Unix pipes
Summary
Uniform representation of sequences, especially input/output files, encourages the development of software tools. File i/o is the simplest example, with all external data as sequences of bytes despite their physical implementation as disk sectors and tape records. Consistent link and load format representations allow incremental linking and program execution. Software tools as defined by Kernighan and Plauger use text files for consistent input and output. This allows several programs to be chained together. Multiple pass programs should produce consistent intermediate files to allow for latter addition or deletion of program passes. (cbb 5/80)
Subtopic: memory as bytes
Quote: pipes with filters require a uniform data format [»kernBW_1975, OK] Quote: in Unix a file is a sequence of bytes no matter what device it resides on [»kernBW1_1979] Quote: expect the output of every program to become the input of other programs; avoid rigid formats, extraneous information, and interactive inputs [»mcilMD7_1978]
Subtopic: resources as file
Quote: IBM 360 generalized machine memory as a sequence of bytes with uniform addressing independent of type [»dehnJC4_1998]
Subtopic: directory as file
Quote: the 8 1/2 windowing system treats all resources as multiplexed files; e.g., /dev/bitblt; X window functionality in 10,000 lines of code [»pikeR6_1991]
Subtopic: well-known name
Quote: by making directories normal files, directory programs are outside of the system [»kernBW1_1979]
Subtopic: file as sequence
Quote: Plan 9 uses the same name for different files/services in different processes; fundamental to system [»pikeR6_2000]
Subtopic: uniform intermediate representation
Quote: a file is an ordered sequence of elements without format; all formatting by higher-level modules or programs [»daleRC_1965] Quote: a file is a linear array of data accessed by name or by segment number plus offset; independent of device Quote: file system implemented in Multics [»daleRC_1965]
Subtopic: strings for conversion
Quote: in multi-pass programs with different intermediate formats, can not remove a pass [»parnDL5_1978]
Quote: SUIT uses string conversion to save data types and to convert between types [»pausR10_1992, OK] Quote: character strings are important for communicating between modules of a large system [»boehHJ12_1995] Quote: desired properties for strings: immutable strings, long strings, files as strings, efficient non-destructive concatenation and substring operations
Topic: file (22 items)
Topic: file input/output (21 items)
Topic: I/O streams (17 items)
Topic: processing a sequence (17 items)
Topic: uniform data model (19 items)
Topic: uniform language systems (25 items)
Topic: software tools (20 items)
Topic: Unix pipes
(10 items)