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>comedi_strerror</H1
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>Name</H2
>comedi_strerror -- return string describing Comedilib error code</DIV
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>Synopsis</H2
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>#include <comedilib.h></PRE
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><CODE
><CODE
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>char * comedi_strerror</CODE
>(int errnum);</CODE
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> Description
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><P
>When a Comedilib function fails, it usually returns -1 or
NULL, depending on the return type. An internal library
variable stores an error number, which can be retrieved with
comedi_errno(). This error number can be converted to a
human-readable form by the functions comedi_perror()
and comedi_strerror().</P
><P
>These functions are intended to mimic the behavior of the
standard C library functions perror(), strerror(), and errno.
In particular, Comedilib functions sometimes return an error
that is generated inside the C library; the comedi error
message in this case is the same as the C library.</P
><P
>The function comedi_strerror() returns a pointer to a
character string
describing the Comedilib error errnum. The persistence
of the returned pointer is undefined, and should not be trusted
after the next Comedilib call. An unrecognized error number will
return a pointer to the string "undefined error", or similar.</P
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