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Microlib does not support all ISO C90 features.
Major ISO C90 features not supported by microlib are:
wcstombs(). All functions defined in Normative Addendum 1 are not supported by microlib.
getenv(). An exception is
clock(). A minimal implementation of
clock()has been provided, which returns only –1, not the elapsed time. You may reimplement
_clock_init(), which it needs), if required.
By default, all the
that interact with a file pointer return an error if called. The only exceptions to
this are the three standard streams
You can change this behavior using
#pragma import(__use_full_stdio). Use of this
pragma provides a microlib version of
supports ANSI C, with only the following exceptions:
EOFindicators are not supported, so
raise()are provided but microlib does not generate signals. The only exception to this is if the program explicitly calls
Floating-point support diverges from IEEE 754 in the following ways, but uses the same data formats and matches IEEE 754 in operations involving only normalized numbers:
fp_status()register in microlib.
argvparameters are undefined and cannot be used to access command-line arguments.