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1 # Package: rdyncall
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2 # File: demo/stdio.R
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3 # Description: Direct I/O of R raw vectors using C stdio functions
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4
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5 dynport(stdio)
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6
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7 # test: fopen returns NULL pointer on error
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8
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9 nonexisting <- "dummyname"
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10 f <- fopen(nonexisting, "r")
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11 is.nullptr(f)
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12
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13 # test: R raw object read/write
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14
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15 tempfile <- "bla"
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16 f <- fopen(tempfile, "wb")
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17 writebuf <- as.raw(0:255)
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18 copy <- writebuf
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19 copy[[1]] <- as.raw(0xFF)
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20 fwrite(writebuf, 1, length(writebuf), f)
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21 fclose(f)
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22
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23 f <- fopen(tempfile, "rb")
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24 readbuf <- raw(256)
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25 copybuf <- readbuf
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26 fread(readbuf, 1, length(readbuf), f)
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27 copybuf[[1]] <- as.raw(0xFF)
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28 fclose(f)
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29
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30 identical(readbuf,writebuf)
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31
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