Translate an error code into a text string, suitable for generating a
diagnostic message.
By convention, all error codes are negative.
The small
values are assumed to be negated versions of the Unix error codes as defined
in
<errno.h>
and the strings returned are as per
strerror(3C).
The larger, negative error codes are
Performance Metrics Application Programming Interface (PMAPI)
error conditions and
pmErrStr(3)
returns an appropriate PMAPI error string, as determined by
code.
The string value is held in a single static buffer, so the returned value is
only valid until the next call to
pmErrStr.