Perl で作る tiny shell

Perl で極限に機能を削った shell の作り方を紹介します

Transcript

1. 1FSMͰ࡞Δ

   UJOZTIFMM
   )PLLBJEPQN
   

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2. !DPEFIFY !$PEF)FY
   w .FSDBSJ *OD
   w %FWFMPQJOHNJDSPTFSWJDFT
   w 0LJOBXBQN
   w *MJLF1FSM94(P
   w IUUQTDPEFIFYIBUFCMPKQ
   

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3. γΣϧͬͯ஌ͬͯ·͔͢
   

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5. /P
   

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6. $ pwd

   

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7. $ pwd

   /Users/codehex
   

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8. #BTI ;TI pTI
   

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9. γΣϧʹ͸

   ༷ʑͳػೳ͕͋Γ·͢
   

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10. ྫ͑͹
    

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11. ύΠϓ
    

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12. $ pwd | cat -n

    

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13. $ pwd | cat -n

    1 /Users/codehex
    

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14. Ξϯυ
    

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15. $ pwd && echo hello

    

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16. $ pwd && echo hello

    /Users/codehex

    hello
    

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17. ͜ΕΒͷ

    ࣮૷Λ஌͍ͬͯ·͔͢ʁ
    

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18. ࠓ೔࿩͢಺༰
    

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19. ࠓ೔࿩͢಺༰
    w ࠷௿ݶͷγΣϧͷఆٛ
    w ߏจղੳ
    w ίϚϯυͷ࣮ߦ
    

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20. ࠓ೔࿩͢಺༰
    w ࠷௿ݶͷγΣϧͷఆٛ
    w ߏจղੳ
    w ίϚϯυͷ࣮ߦ
    

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21. ࠷௿ݶͷγΣϧͷఆٛ
    UJOZTIFMMͷಈ࡞Λఆٛ͢Δ
    

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22. lUJOZTIFMMzNFBOT

    ΊͬͪΌখ͍͞γΣϧ
    

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23. Ͳ͏͍͏ಈ࡞Λ͢Δ͔
    

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24. Ͳ͏͍͏ಈ࡞Λ͢Δ͔
    w ୯ҰίϚϯυͷ࣮ߦ $ ls
    
    w ύΠϓͷ࣮ߦ $ ls | cat
    
    w ΞϯυʹΑΔෳ਺࣮ߦ $ ls && cat
    
    w αϒγΣϧ΍όοΫάϥϯυ࣮ߦ͸ࠓճؚΊ·ͤΜ
    

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25. ࠓ೔࿩͢಺༰
    w ࠷௿ݶͷγΣϧͷఆٛ
    w ߏจղੳ
    w ίϚϯυͷ࣮ߦ
    

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26. ߏจղੳ
    ެจఆٛͱߏจղੳثͷ࡞੒
    

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27. $ cat | cat -n && ls
    

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28. $ cat | cat -n && ls
    

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29. $ cat | cat -n && ls
    

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30. $ cat | cat -n && ls
    

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31. $ cat | cat -n && ls
    

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32. $ cat | cat -n && ls
    ࠨ͔Βӈʹղऍ͠·͢
    

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33. ߏจͷఆٛ
    

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34. ӈʹ࿈͍݁ͯ͘͠Α͏ʹ

    ఆٛ෇͚Λߦ͏
    

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35. ߏจఆٛ
    • CMD: [a-zA-Z_-][0-9a-zA-Z_-]*
    • ARG: [0-9a-zA-Z_-]* | [0-9a-zA-Z_-]*
    • SHLL: '&&' |
    • PIPE: '|' |
    • AND: '&&' |
    

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36. ߏจղੳثͷ࡞੒
    

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37. ߏจղੳثʹඞཁͳཁૉ
    

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38. ߏจղੳثʹඞཁͳཁૉ
    w จࣈྻͷεΩϟφʔ
    w ಡΈࠐΈҐஔ΍ಡΈऔͬͨจࣈྻΛอ࣋͢Δ
    w จࣈྻͷϚονϯά
    w εΩϟφʔͰಘͨจࣈྻ͕ߏจఆٛʹϚονͨ͠
    ͔Ͳ͏͔൑ผ͢Δ
    w Ϛονͨ͠จࣈྻʹҙຯΛ΋ͨͤΔ τʔΫϯԽ
    
    w ߏจ໦ͷੜ੒
    

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39. 1FSMͰ͸ʁ
    

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40. ਖ਼نදݱ
    

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41. IUUQTQFSMEPDQFSMPSHQFSMPQIUNMD(@BTTFSUJPO@
    l"VTFGVMJEJPNGPSAlexAMJLF

    TDBOOFSTJTA/\G…/gcAʜz
    

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42. /\G…/gc
    

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43. /\G…/gc
    w A/cANPEJpFSͰ͸ݱࡏϚον͍ͯ͠ΔҐஔΛ

    อ࣋͢Δ͜ͱ͕Ͱ͖Δɻ
    • pos()ͰҐஔΛऔΓग़͢͜ͱ͕Մೳ
    • \GͰલճAm//gAͰϚονͨ͠ҐஔΛอ࣋͢Δ͜ͱ
    ͕Մೳ
    

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44. εΩϟφʔͱϚονϯάͷ

    ໾ׂΛ΋ͭ͜ͱ͕Ͱ͖Δ ?P?
    W
    

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45. ͜͜Ͱྑ͍৘ใ
    

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46. ΊͬͪΌࢀߟʹͳΔϖʔδ
    w IUUQTHJUIVCDPNLBSVQBOFSVSBQ
    +40/CMPCNBTUFSMJC+40/1BSTFSQN
    w IUUQTHJUIVCDPNLBSVQBOFSVSB50.-
    1BSTFSCMPCNBTUFSMJC50.-1BSTFSQN
    

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47. ࣮૷༷ࢠ
    

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48. ߏจఆٛ
    • CMD: [a-zA-Z_-][0-9a-zA-Z_-]*
    • ARG: [0-9a-zA-Z_-]* | [0-9a-zA-Z_-]*
    • SHLL: '&&' |
    • PIPE: '|' |
    • AND: '&&' |
    

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49. $.%
    

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50. ߏจఆٛ
    • CMD: [a-zA-Z_-][0-9a-zA-Z_-]*
    • ARG: [0-9a-zA-Z_-]* | [0-9a-zA-Z_-]*
    • SHLL: '&&' |
    • PIPE: '|' |
    • AND: '&&' |
    

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51. 4)--
    

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52. ߏจఆٛ
    • CMD: [a-zA-Z_-][0-9a-zA-Z_-]*
    • ARG: [0-9a-zA-Z_-]* | [0-9a-zA-Z_-]*
    • SHLL: '&&' |
    • PIPE: '|' |
    • AND: '&&' |
    

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53. 1*1&
    

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54. ߏจఆٛ
    • CMD: [a-zA-Z_-][0-9a-zA-Z_-]*
    • ARG: [0-9a-zA-Z_-]* | [0-9a-zA-Z_-]*
    • SHLL: '&&' |
    • PIPE: '|' |
    • AND: '&&' |
    

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55. "/%
    

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56. ໦ΛQSJOU༷ͨ͠ࢠ
    $ cat | cat -n && ls
    

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57. "/%
    1*1&
    DBU
    DBU
    MT
    $ cat | cat -n && ls
    

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58. ͪͳΈʹ
    

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59. $ cat | cat -n && ls
    

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60. $ cat | cat -n && ls
    ࠨ͔Βӈʹղऍ͠·͢
    

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61. ͳͷͰ

    ໦ΛḷΔͱ͖͸
    

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62. "/%
    1*1&
    DBU
    DBU
    MT
    $ cat | cat -n && ls
    ᶃ
    

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63. "/%
    1*1&
    DBU
    DBU
    MT
    $ cat | cat -n && ls
    ᶃ ᶄ
    ᶅ
    

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64. "/%
    1*1&
    DBU
    DBU
    MT
    $ cat | cat -n && ls
    ᶃ ᶄ
    ᶅ
    ᶆ ᶇ
    

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65. ͜ΕΛجʹ

    ࣮ߦ͢ΔػೳΛ࡞੒͠·͢
    

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66. ࠓ೔࿩͢಺༰
    w ࠷௿ݶͷγΣϧͷఆٛ
    w ߏจղੳ
    w ίϚϯυͷ࣮ߦ
    

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67. ίϚϯυͷ࣮ߦ
    ߏจ໦Λجʹ࣮ߦ͢Δ
    

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68. ࣮૷ͷલʹ
    

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69. ඪ४ετϦʔϜʹ͍ͭͯ
    

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70. w 45%*/ 4UBOEBSE*OQVU
    ඪ४ೖྗ
    w 45%065 4UBOEBSE0VUQVU
    ඪ४ग़ྗ
    w 45%&33 4UBOEBSE&SSPS
    ඪ४Τϥʔग़ྗ
    ඪ४ετϦʔϜ
    

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71. ͜ΕΒ͸࣮࣭

    ϑΝΠϧͱͯ͠ѻΘΕ·͢
    

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72. ୯ҰίϚϯυͷ

    ετϦʔϜͷϑϩʔ
    

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73. $ cat
    

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74. $ cat
    cat
    45%*/
    

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75. $ cat
    cat
    45%*/
    45%065
    45%&33
    

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76. $ cat
    GPSLΛ࢖͏ͱTIΛհ͞ͳ͍Ͱ࣮ߦՄೳ
    

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77. ύΠϓͷϑϩʔ
    

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78. $ fortune | cowsay
    

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79. $ fortune | cowsay
    45%*/
    PS/PU
    ᶃ
    

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80. $ fortune | cowsay
    45%*/
    PS/PU
    45%065
    ᶃ ᶄ
    

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81. $ fortune | cowsay
    45%*/
    PS/PU
    45%065 45%*/
    ᶃ ᶄ ᶅ
    

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82. $ fortune | cowsay
    45%*/
    PS/PU
    45%065 45%*/ 45%065
    ᶃ ᶄ ᶅ ᶆ
    

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83. ͜ΕΒͷίϚϯυ͸

    ผϓϩηεͰಈ͍͍ͯ·͢
    

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84. $ ps a | cat
    1*%
    

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85. ύΠϓͷ࣮૷
    

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86. pipe my ($r, $w);
    

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87. w $r͕3FBEFS $w͕8SJUFS
    w 8SJUFSʹσʔλ͕ॻ͖ࠐ·Εͨͱ͖

    3FBEFSͰͦͷσʔλΛಡΈऔΔ͜ͱ͕Մೳ
    pipe my ($r, $w);
    

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88. ֤ϓϩηεؒͷετϦʔϜΛ

    pipe()Ͱܨ͛Δ͜ͱͰ࣮૷Մೳ
    

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89. ͦͷ࣌ͷϑϩʔ
    

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90. $ fortune | cowsay
    45%*/
    PS/PU
    45%065
    ᶃ ᶄ
    

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91. $ fortune | cowsay
    45%*/
    PS/PU
    45%065
    ᶃ ᶄ ᶅ ᶆ
    8SJUFS
    3FBEFS
    

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92. $ fortune | cowsay
    45%*/
    PS/PU
    45%065 45%*/ 45%065
    ᶃ ᶄ ᶅ ᶆ
    8SJUFS
    3FBEFS
    ᶇ
    ᶈ ᶉ
    

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93. ͳͷͰ࣮࣭

    ͜ͷΑ͏ʹߟ͑ΒΕΔ
    

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94. $ fortune | cowsay
    45%*/
    PS/PU
    8SJUFS 3FBEFS 45%065
    ᶃ ᶄ ᶅ ᶆ
    

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96. w ίϚϯυOPEFͰ͔ͭ਌OPEF͕ύΠϓͰ͸ͳ͍

    ৔߹͸ଈίϚϯυΛ࣮ߦ
    w ͦΕҎ֎͸ίϚϯυΛอ࣋͢Δ
    w ύΠϓOPEF͔ͭ਌͕ύΠϓOPEFͰ͸ͳ͍৔߹

    อ࣋͠ଓ͚ͨίϚϯυΛ࣮ߦ
    

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97. Ξϯυͷϑϩʔ
    

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98. $ echo hello && echo world
    

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99. $ echo hello && echo world
    ᶃ
    

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100. $ echo hello && echo world
     ᶃ ᶄ
     

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101. w ΞϯυOPEFʹདྷΔ·ͰʹࠨͷOPEFΛ

     શ࣮ͯߦ͢Δ
     w ੒ޭͨ͠৔߹ӈͷOPEFΛࠨͷOPEFͱಉ͡Α͏
     ʹ࣮ߦ͢Δ
     

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102. ͜Ε͚ͩͰ

     UJOZTIFMM͕׬੒͠·͢ʂ
     

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103. ·ͱΊ
     

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104. ·ͱΊ
     w ӈʹ࿈͍݁ͯ͘͠Α͏ʹߏจఆٛͨ͠
     w γΣϧͷύΠϓɺΞϯυػೳΛཧղͯ͠ɺղੳ࣌ʹ
     ࣮ߦ͢ΔػೳΛ࡞੒ͨ͠
     

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105. ࣭໰Ͳ͏ͧ
     https://github.com/Code-Hex/p5-Shell-Tiny
     

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