Error read() on macOS arm64

[Wolfram]

Hello,

why do get I this error on an ARM Mac?
"error: call to undeclared function 'read'; ISO C99 and later do not support implicit function declarations [-Wimplicit-function-declaration]"
On an Intel Mac the same code works.

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! read(serialPort, p_buffer, 4);

[Fred]

You need to declare it with clang (or include the .h)

[Wolfram]

If I include it like this I get an error "clang: warning: treating 'c-header' input as 'c++-header' when in C++ mode, this behavior is deprecated [-Wdeprecated]
clang: error: cannot specify -o when generating multiple output files"

Code: Select all

ImportC "unistd.h"
  read_(fd, p_buf, size)
EndImport

[Quin]

I haven't tried this, but what if you do it with inline c?
like:

Code: Select all

! #include <unistd.h>

[Fred]

You can try

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ImportC ""
  read_(fd, p_buf, size)
EndImport

[Wolfram]

This example works

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ImportC ""
    _read_(port, *read_buf, size) 
EndImport
  
  read_(port, *read_buf, size) 

But how can use the C code to include th .h file?
This example does not work on my ARM Mac and why does the C function red() works without including on my Intel Mac ?

Code: Select all

! #include <unistd.h>
! read(v_serialport, p_buffer, 4);

[ricardo_sdl]

You can try

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ImportC ""
  read_(fd, p_buf, size)
EndImport

What does the empty string after ImportC imply or mean?

[Quin]

You can try

Code: Select all

ImportC ""
  read_(fd, p_buf, size)
EndImport

What does the empty string after ImportC imply or mean?

It means you're importing a function from a library PB has already imported, just the function itself hasn't been imported.