|Perl Language Reference Manual|
by Larry Wall and others
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25 perldiag: Various Perl diagnostics
These messages are classified as follows (listed in increasing order of desperation):
(W) A warning (optional). (D) A deprecation (enabled by default). (S) A severe warning (enabled by default). (F) A fatal error (trappable). (P) An internal error you should never see (trappable). (X) A very fatal error (nontrappable). (A) An alien error message (not generated by Perl).
The majority of messages from the first three classifications above
(W, D & S) can be controlled using the
If a message can be controlled by the
warnings pragma, its warning
category is included with the classification letter in the description
Optional warnings are enabled by using the
warnings pragma or the -w
and -W switches. Warnings may be captured by setting
to a reference to a routine that will be called on each warning instead
of printing it. See 10.
Severe warnings are always enabled, unless they are explicitly disabled
warnings pragma or the -X switch.
Trappable errors may be trapped using the eval operator. See
. In almost all cases, warnings may be selectively
disabled or promoted to fatal errors using the
See "Perl pragma to control optional warnings" (warnings) in the Perl Library Reference Manual (Volume 1).
The messages are in alphabetical order, without regard to upper or lower-case. Some of these messages are generic. Spots that vary are denoted with a %s or other printf-style escape. These escapes are ignored by the alphabetical order, as are all characters other than letters. To look up your message, just ignore anything that is not a letter.