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1 Alex Smith, 26 March 2008
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2
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3 syslibc.c is an example of a C program designed to be used with the
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4 INTERCAL external call code. It only attempts to emulate the base 2
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5 algorithms, but in a base 2 program it should be a valid drop-in
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6 replacement for the real system library. (Don't forget to use the -eE
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7 options when linking this to an INTERCAL program; -e to allow C
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8 programs to be linked in, and -E to suppress the 'real' syslib.)
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9
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10 The library is designed foremost to ensure that all errors are checked
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11 (as they would be in the INTERCAL, although you get the error messages
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12 produced by C code), and secondarily for speed (it is substantially
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13 faster than the INTERCAL version of the system library, but that isn't
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14 particularly surprising).
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15
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16 Note that some INTERCAL programs rely on undocumented features of the
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17 system library; I have implemented the commonly-used (1001), but some
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18 of the example programs (for instance primes.i) NEXT to other
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19 undocumented internal lines of syslib.i, and such programs will error
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20 out on the C version of the syslib.
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21
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22 There are some situations in which the C program will cause errors,
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23 but the INTERCAL version wouldn't; remember that any attempt to alter
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24 or view an INTERCAL variable from C code causes an error if that
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25 variable doesn't exist in the INTERCAL program. Therefore, in order to
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26 use a particular routine, you should mention all the variables that
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27 are its inputs and outputs somewhere in your INTERCAL program; in
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28 particular, if you're using overflow-checked routines, make sure you
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29 mention .4 at least once in your program.
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