Use curses, don't swear by Sean Zicari

Transcript

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2. Use curses...
   don't swear
   an overview of terminal control in python
   

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3. . Web Developer
   . Love all things low level
   . Love computer history
   whoami
   

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4. . Web Developer
   . Love all things low level
   . Love computer history
   whoami
   

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5. . Web Developer
   . Love all things low level
   . Love computer history
   whoami
   

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6. . Cars.com
   . PyCon sponsor
   . Python/Postgres shop
   . Awesome place to work!
   where do I work
   

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7. . Cars.com
   . PyCon sponsor
   . Python/Postgres shop
   . Awesome place to work!
   where do I work
   

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8. . Cars.com
   . PyCon sponsor
   . Python/Postgres shop
   . Awesome place to work!
   where do I work
   

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9. . Cars.com
   . PyCon sponsor
   . Python/Postgres shop
   . Awesome place to work!
   where do I work
   

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10. video terminals!
    

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11. . First VT ~1969
    . Basic line/screen control
    . ASCII character set
    . ~300 baud (characters/second)
    video terminals!
    

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12. . First VT ~1970
    . Basic line control
    . ASCII character set
    . ~300 baud (characters/second)
    video terminals!
    VT-100
    

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13. . Kernel handled data transfer
    . Terminal handled display
    (cursor, color, line handling...)
    . Terminal control through escape
    sequences
    talking to a terminal
    

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14. . Vendor-specific escape sequences
    . ECMA-48 adopted in 1976
    . termcap released in 1978
    (TERMinal CAPability)
    standards? nope.
    Esc[20h Set new line mode LMN
    Esc[?1h Set cursor key to
    application
    DECCKM
    none Set ANSI (versus
    VT52)
    DECANM
    Esc[?3h Set number of
    columns to 132
    DECCOLM
    Esc[?4h Set smooth scrolling DECSCLM
    Esc[?5h Set reverse video on
    screen
    DECSCNM
    Esc[?6h Set origin to relative DECOM
    Esc[?7h Set auto-wrap mode DECAWM
    Esc[?8h Set auto-repeat mode DECARM
    Esc[?9h Set interlacing mode DECINLM
    

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15. . Vendor-specific escape sequences
    . ECMA-48 adopted in 1976
    . termcap released in 1978
    (TERMinal CAPability)
    standards? nope.
    

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16. . Vendor-specific escape sequences
    . ECMA-48 adopted in 1976
    . termcap released in 1978
    (TERMinal CAPability)
    standards? nope.
    

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17. line discipline
    

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18. line discipline
    . Glue code
    . No execution context
    . line modes: "raw" or "cooked"
    

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19. introducing (n)curses
    . Developed for BSD
    . Code borrowed from vi
    . Originally used termcap
    . Unix System III / V
    . Gained additional features
    . Curses became pcurses
    . pcurses became n(ew)curses
    

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20. why (n)curses?
    . Plethora of terminals
    . Plethora of escape sequence variations
    . Portable
    . Convenient abstractions
    . Standardized API
    

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21. (n)curses philosophy
    . Tools provided...
    . ...but you're on your own
    . One primary object: stdscr
    . Full cursor/screen control
    . Forms, windows, colors, cbreak mode
    . Manual Screen refresh
    

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22. program dissection
    

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23. program dissection
    

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24. program dissection
    

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25. program dissection
    

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26. program dissection
    

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27. program dissection
    

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28. program dissection
    

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29. program dissection
    

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30. . Pronounced "oor'-wid"
    . Layered architecture
    . Display modules
    . Widget layout
    . Event loops
    introducing urwid
    

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31. . Pronounced "oor'-wid"
    . Layered architecture
    . Display modules
    . Widget layout
    . Event loops
    introducing urwid
    

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32. . Pronounced "oor'-wid"
    . Layered architecture
    . Display modules
    . Widget layout
    . Event loops
    introducing urwid
    

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33. . Pronounced "oor'-wid"
    . Layered architecture
    . Display modules
    . Widget layout
    . Event loops
    introducing urwid
    

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34. . Pronounced "oor'-wid"
    . Layered architecture
    . Display modules
    . Widget layout
    . Event loops
    introducing urwid
    

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35. program dissection
    

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36. resources
    Python Curses
    -------------
    . Documentation
    http://docs.python.org/2/library/curses.html
    . Tutorial
    http://docs.python.org/2/howto/curses.html
    Urwid
    -----
    . Documentation
    http://excess.org/urwid/docs/
    . Tutorials
    http://excess.org/urwid/docs/tutorial/index.html#urwid-tutorial
    . Manual
    http://excess.org/urwid/docs/manual/index.html#urwid-manual
    

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