Optional warnings are enabled by using the B<-w> switch. Warnings may
be captured by setting C<$SIG{__WARN__}> to a reference to a routine that
will be called on each warning instead of printing it. See L<perlvar>.
+
Trappable errors may be trapped using the eval operator. See
-L<perlfunc/eval>.
+L<perlfunc/eval>. In almost all cases, warnings may be selectively
+disabled or promoted to fatal errors using the C<warnings> pragma.
+See L<warnings>.
Some of these messages are generic. Spots that vary are denoted with a %s,
just as in a printf format. Note that some messages start with a %s!
-The symbols C<"%(-?@> sort before the letters, while C<[> and C<\> sort after.
+Since the messages are listed in alphabetical order, the symbols
+C<"%(-?@> sort before the letters, while C<[> and C<\> sort after.
=over 4
+=item "my sub" not yet implemented
+
+(F) Lexically scoped subroutines are not yet implemented. Don't try that
+yet.
+
=item "my" variable %s can't be in a package
(F) Lexically scoped variables aren't in a package, so it doesn't make sense
(F) The '!' is allowed in pack() and unpack() only after certain types.
See L<perlfunc/pack>.
+=item # cannot take a count
+
+(F) You had an unpack template indicating a counted-length string,
+but you have also specified an explicit size for the string.
+See L<perlfunc/pack>.
+
+=item # must be followed by a, A or Z
+
+(F) You had an unpack template indicating a counted-length string,
+which must be followed by one of the letters a, A or Z
+to indicate what sort of string is to be unpacked.
+See L<perlfunc/pack>.
+
+=item # must be followed by a*, A* or Z*
+
+(F) You had an pack template indicating a counted-length string,
+Currently the only things that can have their length counted are a*, A* or Z*.
+See L<perlfunc/pack>.
+
+=item # must follow a numeric type
+
+(F) You had an unpack template that contained a '#',
+but this did not follow some numeric unpack specification.
+See L<perlfunc/pack>.
+
=item % may only be used in unpack
(F) You can't pack a string by supplying a checksum, because the
checksumming process loses information, and you can't go the other
way. See L<perlfunc/unpack>.
+=item Repeat count in pack overflows
+
+(F) You can't specify a repeat count so large that it overflows
+your signed integers. See L<perlfunc/pack>.
+
+=item Repeat count in unpack overflows
+
+(F) You can't specify a repeat count so large that it overflows
+your signed integers. See L<perlfunc/unpack>.
+
=item /%s/: Unrecognized escape \\%c passed through
(W) You used a backslash-character combination which is not recognized
by Perl. This combination appears in an interpolated variable or a
C<'>-delimited regular expression.
+=item /%s/ should probably be written as "%s"
+
+(W) You have used a pattern where Perl expected to find a string,
+like in the first argument to C<join>. Perl will treat the true
+or false result of matching the pattern against $_ as the string,
+which is probably not what you had in mind.
+
=item %s (...) interpreted as function
(W) You've run afoul of the rule that says that any list operator followed
by parentheses turns into a function, with all the list operators arguments
found inside the parentheses. See L<perlop/Terms and List Operators (Leftward)>.
+=item %s() called too early to check prototype
+
+(W) You've called a function that has a prototype before the parser saw a
+definition or declaration for it, and Perl could not check that the call
+conforms to the prototype. You need to either add an early prototype
+declaration for the subroutine in question, or move the subroutine
+definition ahead of the call to get proper prototype checking. Alternatively,
+if you are certain that you're calling the function correctly, you may put
+an ampersand before the name to avoid the warning. See L<perlsub>.
+
=item %s argument is not a HASH element
(F) The argument to exists() must be a hash element, such as
(S) The symbol in question was declared but somehow went out of scope
before it could possibly have been used.
+=item %s package attribute may clash with future reserved word: %s
+
+(W) A lowercase attribute name was used that had a package-specific handler.
+That name might have a meaning to Perl itself some day, even though it
+doesn't yet. Perhaps you should use a mixed-case attribute name, instead.
+See L<attributes>.
+
=item %s syntax OK
(F) The final summary message when a C<perl -c> succeeds.
To silently interpret it as the Perl operator, use the C<CORE::> prefix
on the operator (e.g. C<CORE::log($x)>) or by declaring the subroutine
-to be an object method (see L<attrs>).
+to be an object method (see L<perlsub/"Subroutine Attributes">
+or L<attributes>).
=item Args must match #! line
SvREFCNT_inc() was called too few times, or that the SV was mortalized
when it shouldn't have been, or that memory has been corrupted.
+=item Attempt to join self
+
+(F) You tried to join a thread from within itself, which is an
+impossible task. You may be joining the wrong thread, or you may
+need to move the join() to some other thread.
+
=item Attempt to pack pointer to temporary value
(W) You tried to pass a temporary value (like the result of a
could not be guaranteed (due to the errors), and since subsequent code
likely depends on its correct operation, Perl just gave up.
+=item Binary number > 0b11111111111111111111111111111111 non-portable
+
+(W) The binary number you specified is larger than 2**32-1
+(4294967295) and therefore non-portable between systems. See
+L<perlport> for more on portability concerns.
+
=item bind() on closed fd
(W) You tried to do a bind on a closed socket. Did you forget to check
the return value of your socket() call? See L<perlfunc/bind>.
-=item Bizarre copy of %s in %s
+=item Bit vector size > 32 non-portable
-(P) Perl detected an attempt to copy an internal value that is not copiable.
+(W) Using bit vector sizes larger than 32 is non-portable.
-=item Buffer overflow in prime_env_iter: %s
+=item Bizarre copy of %s in %s
-(W) A warning peculiar to VMS. While Perl was preparing to iterate over
-%ENV, it encountered a logical name or symbol definition which was too long,
-so it was truncated to the string shown.
+(P) Perl detected an attempt to copy an internal value that is not copiable.
=item Buffer overflow in prime_env_iter: %s
missing. You need to figure out where your CRTL misplaced its environ
or define F<PERL_ENV_TABLES> (see L<perlvms>) so that environ is not searched.
-=item Can't read CRTL environ
-
-(S) A warning peculiar to VMS. Perl tried to read an element of %ENV
-from the CRTL's internal environment array and discovered the array was
-missing. You need to figure out where your CRTL misplaced its environ
-or define F<PERL_ENV_TABLES> (see L<perlvms>) so that environ is not searched.
-
=item Can't "redo" outside a block
(F) A "redo" statement was executed to restart the current block, but
from a deleted (but still opened) file. You have to say C<-i.bak>, or some
such.
-=item Can't do inplace edit: %s E<gt> 14 characters
+=item Can't do inplace edit: %s would not be unique
-(S) There isn't enough room in the filename to make a backup name for the file.
+(S) Your filesystem does not support filenames longer than 14
+characters and Perl was unable to create a unique filename during
+inplace editing with the B<-i> switch. The file was ignored.
=item Can't do inplace edit: %s is not a regular file
(F) You aren't allowed to assign to the item indicated, or otherwise try to
change it, such as with an auto-increment.
+=item Can't modify non-lvalue subroutine call
+
+(F) Subroutines used in lvalue context should be marked as such, see
+L<perlsub/"Lvalue subroutines">.
+
=item Can't modify nonexistent substring
(P) The internal routine that does assignment to a substr() was handed
was currently active, which is not allowed. If you really want to do
this, you should write C<sort { &func } @x> instead of C<sort func @x>.
+=item Can't remove %s: %s, skipping file
+
+(S) You requested an inplace edit without creating a backup file. Perl
+was unable to remove the original file to replace it with the modified
+file. The file was left unmodified.
+
=item Can't rename %s to %s: %s, skipping file
-(S) The rename done by the B<-i> switch failed for some reason, probably because
-you don't have write permission to the directory.
+(S) The rename done by the B<-i> switch failed for some reason,
+probably because you don't have write permission to the directory.
=item Can't reopen input pipe (name: %s) in binary mode
(F) The return statement was executed in mainline code, that is, where
there was no subroutine call to return out of. See L<perlsub>.
+=item Can't return %s from lvalue subroutine
+
+(F) Perl detected an attempt to return illegal lvalues (such
+as temporary or readonly values) from a subroutine used as an lvalue.
+This is not allowed.
+
=item Can't stat script "%s"
(P) For some reason you can't fstat() the script even though you have
=item Character class syntax [%s] belongs inside character classes
(W) The character class constructs [: :], [= =], and [. .] go
-I<inside> character classes, the [] are part of the construct. For
-example: /[[:alpha:]]/
+I<inside> character classes, the [] are part of the construct,
+for example: /[012[:alpha:]345]/. Note that the last two constructs
+are not currently implemented, they are placeholders for future extensions.
-=item Character class syntax [ .] is reserved for future extensions
+=item Character class syntax [. .] is reserved for future extensions
(W) Within regular expression character classes ([]) the syntax beginning
with "[." and ending with ".]" is reserved for future extensions.
inlining. See L<perlsub/"Constant Functions"> for commentary and
workarounds.
+=item constant(%s): %%^H is not localized
+
+(F) When setting compile-time-lexicalized hash %^H one should set the
+corresponding bit of $^H as well.
+
+=item constant(%s): %s
+
+(F) Compile-time-substitutions (such as overloaded constants and
+character names) were not correctly set up.
+
=item Copy method did not return a reference
(F) The method which overloads "=" is buggy. See L<overload/Copy Constructor>.
(W) You redefined a format. To suppress this warning, say
{
- no warning;
+ no warnings;
eval "format NAME =...";
}
(D) Really old Perl let you omit the % on hash names in some spots. This
is now heavily deprecated.
+=item Hexadecimal number > 0xffffffff non-portable
+
+(W) The hexadecimal number you specified is larger than 2**32-1
+(4294967295) and therefore non-portable between systems. See
+L<perlport> for more on portability concerns.
+
=item Identifier too long
(F) Perl limits identifiers (names for variables, functions, etc.) to
(W) You may have tried to use an 8 or 9 in a octal number. Interpretation
of the octal number stopped before the 8 or 9.
-=item Illegal hex digit %s ignored
+=item Illegal hexadecimal digit %s ignored
-(W) You may have tried to use a character other than 0 - 9 or A - F in a
-hexadecimal number. Interpretation of the hexadecimal number stopped
+(W) You may have tried to use a character other than 0 - 9 or A - F, a - f
+in a hexadecimal number. Interpretation of the hexadecimal number stopped
before the illegal character.
+=item Illegal number of bits in vec
+
+(F) The number of bits in vec() (the third argument) must be a power of
+two from 1 to 32 (or 64, if your platform supports that).
+
=item Illegal switch in PERL5OPT: %s
(X) The PERL5OPT environment variable may only be used to set the
=item Integer overflow in %s number
-(S) The literal hex, octal or binary number you have specified is
-too big for your architecture. On a 32-bit architecture the largest
-literal hex, octal or binary number representable without overflow
-is 0xFFFFFFFF, 037777777777, or 0b11111111111111111111111111111111
-respectively. Note that Perl transparently promotes decimal literals
-to a floating point representation internally--subject to loss of
-precision errors in subsequent operations--so this limit usually
-doesn't apply to decimal literals.
+(W) The hexadecimal, octal or binary number you have specified either
+as a literal in your code or as a scalar is too big for your
+architecture, and has been converted to a floating point number. On a
+32-bit architecture the largest hexadecimal, octal or binary number
+representable without overflow is 0xFFFFFFFF, 037777777777, or
+0b11111111111111111111111111111111 respectively. Note that Perl
+transparently promotes all numbers to a floating point representation
+internally--subject to loss of precision errors in subsequent
+operations.
=item Internal inconsistency in tracking vforks
(P) Something went badly awry in the regular expression parser.
+=item Invalid %s attribute: %s
+
+The indicated attribute for a subroutine or variable was not recognized
+by Perl or by a user-supplied handler. See L<attributes>.
+
+=item Invalid %s attributes: %s
+
+The indicated attributes for a subroutine or variable were not recognized
+by Perl or by a user-supplied handler. See L<attributes>.
+
=item invalid [] range in regexp
(F) The range specified in a character class had a minimum character
-greater than the maximum character. See L<perlre>.
+greater than the maximum character, or the range didn't start/end with
+a literal character. See L<perlre>.
=item Invalid conversion in %s: "%s"
(W) Perl does not understand the given format conversion.
See L<perlfunc/sprintf>.
+=item Invalid separator character %s in attribute list
+
+(F) Something other than a comma or whitespace was seen between the
+elements of an attribute list. If the previous attribute
+had a parenthesised parameter list, perhaps that list was terminated
+too soon. See L<attributes>.
+
=item Invalid type in pack: '%s'
(F) The given character is not a valid pack type. See L<perlfunc/pack>.
(W) You tried to do a listen on a closed socket. Did you forget to check
the return value of your socket() call? See L<perlfunc/listen>.
+=item Lvalue subs returning %s not implemented yet
+
+(F) Due to limitations in the current implementation, array and hash
+values cannot be returned in subroutines used in lvalue context.
+See L<perlsub/"Lvalue subroutines">.
+
=item Method for operation %s not found in package %s during blessing
(F) An attempt was made to specify an entry in an overloading table that
mentioned with the $ in Perl, unlike in the shells, where it can vary from
one line to the next.
+=item Missing %sbrace%s on \N{}
+
+(F) Wrong syntax of character name literal C<\N{charname}> within
+double-quotish context.
+
=item Missing comma after first argument to %s function
(F) While certain functions allow you to specify a filehandle or an
(W) Multidimensional arrays aren't written like C<$foo[1,2,3]>. They're written
like C<$foo[1][2][3]>, as in C.
+=item Missing name in "my sub"
+
+(F) The reserved syntax for lexically scoped subroutines requires that they
+have a name with which they can be found.
+
=item Name "%s::%s" used only once: possible typo
(W) Typographical errors often show up as unique variable names.
to translate to the number of seconds which need to be added to UTC to
get local time.
-=item no UTC offset information; assuming local time is UTC
-
-(S) A warning peculiar to VMS. Per was unable to find the local
-timezone offset, so it's assuming that local system time is equivalent
-to UTC. If it's not, define the logical name F<SYS$TIMEZONE_DIFFERENTIAL>
-to translate to the number of seconds which need to be added to UTC to
-get local time.
-
=item Not a CODE reference
(F) Perl was trying to evaluate a reference to a code value (that is, a
Perl are likely to eliminate this arbitrary limitation. In the meantime,
try using scientific notation (e.g. "1e6" instead of "1_000_000").
+=item Octal number > 037777777777 non-portable
+
+(W) The octal number you specified is larger than 2**32-1 (4294967295)
+and therefore non-portable between systems. See L<perlport> for more
+on portability concerns.
+
+See also L<perlport> for writing portable code.
+
=item Odd number of elements in hash assignment
(S) You specified an odd number of elements to initialize a hash, which
(W) You redefined a subroutine. To suppress this warning, say
{
- no warning;
+ no warnings;
eval "sub name { ... }";
}
L<perlvms>) so that the environ array isn't the target of the change to
%ENV which produced the warning.
-=item This Perl can't reset CRTL eviron elements (%s)
-
-=item This Perl can't set CRTL environ elements (%s=%s)
-
-(W) Warnings peculiar to VMS. You tried to change or delete an element
-of the CRTL's internal environ array, but your copy of Perl wasn't
-built with a CRTL that contained the setenv() function. You'll need to
-rebuild Perl with a CRTL that does, or redefine F<PERL_ENV_TABLES> (see
-L<perlvms>) so that the environ array isn't the target of the change to
-%ENV which produced the warning.
-
=item times not implemented
(F) Your version of the C library apparently doesn't do times(). I suspect
(F) There are no byte-swapping functions for a machine with this byte order.
-=item Unknown process %x sent message to prime_env_iter: %s
+=item Unknown open() mode '%s'
-(P) An error peculiar to VMS. Perl was reading values for %ENV before
-iterating over it, and someone else stuck a message in the stream of
-data Perl expected. Someone's very confused, or perhaps trying to
-subvert Perl's population of %ENV for nefarious purposes.
+(F) The second argument of 3-arguments open is not one from the list
+of C<L<lt>>, C<L<gt>>, C<E<gt>E<gt>>, C<+L<lt>>, C<+L<gt>>,
+C<+E<gt>E<gt>>, C<-|>, C<|-> of possible open() modes.
=item Unknown process %x sent message to prime_env_iter: %s
finding it. Chances are you left some needed parentheses out earlier in
the line, and you really meant a "less than".
+=item Unterminated attribute parameter in attribute list
+
+(F) The lexer saw an opening (left) parenthesis character while parsing an
+attribute list, but the matching closing (right) parenthesis
+character was not found. You may need to add (or remove) a backslash
+character to get your parentheses to balance. See L<attributes>.
+
+=item Unterminated attribute list
+
+(F) The lexer found something other than a simple identifier at the start
+of an attribute, and it wasn't a semicolon or the start of a
+block. Perhaps you terminated the parameter list of the previous attribute
+too soon. See L<attributes>.
+
=item Use of $# is deprecated
(D) This was an ill-advised attempt to emulate a poorly defined B<awk> feature.
than 1024 characters. The return value has been truncated to 1024
characters.
-=item Value of CLI symbol "%s" too long
-
-(W) A warning peculiar to VMS. Perl tried to read the value of an %ENV
-element from a CLI symbol table, and found a resultant string longer
-than 1024 characters. The return value has been truncated to 1024
-characters.
-
=item Variable "%s" is not imported%s
(F) While "use strict" in effect, you referred to a global variable