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>comedi_perror</H1
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>Name</H2
>comedi_perror -- print a Comedilib error message</DIV
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>Synopsis</H2
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>#include <comedilib.h></PRE
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><CODE
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>void comedi_perror</CODE
>(const char * s);</CODE
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> Description
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>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_perror() prints an error message to stderr.
The error message consists of the argument string, a colon, a
space, a description of the error condition, and a new line.</P
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