    (W) A warning (optional).
    (D) A deprecation (optional).
    (S) A severe warning (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 warnings pragma.

If a message can be controlled by the warnings pragma, its warning category is included with the classification letter in the description below.

Optional warnings are enabled by using the warnings pragma or the -w and -W switches. Warnings may be captured by setting $SIG{__WARN__} to a reference to a routine that will be called on each warning instead of printing it. See the perlvar manpage.

Default warnings are always enabled unless they are explicitly disabled with the warnings pragma or the -X switch.

Trappable errors may be trapped using the eval operator. See eval in the perlfunc manpage. In almost all cases, warnings may be selectively disabled or promoted to fatal errors using the warnings pragma. See the warnings manpage.

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.

accept() on closed socket %s

(W closed) You tried to do an accept on a closed socket. Did you forget to check the return value of your socket() call? See accept in the perlfunc manpage.

Allocation too large: %lx

(X) You can't allocate more than 64K on an MS-DOS machine.

'!' allowed only after types %s

(F) The '!' is allowed in pack() and unpack() only after certain types. See pack in the perlfunc manpage.

Ambiguous call resolved as CORE::%s(), qualify as such or use &

(W ambiguous) A subroutine you have declared has the same name as a Perl keyword, and you have used the name without qualification for calling one or the other. Perl decided to call the builtin because the subroutine is not imported.

To force interpretation as a subroutine call, either put an ampersand before the subroutine name, or qualify the name with its package. Alternatively, you can import the subroutine (or pretend that it's imported with the use subs pragma).

To silently interpret it as the Perl operator, use the CORE:: prefix on the operator (e.g. CORE::log($x)) or by declaring the subroutine to be an object method (see Subroutine Attributes in the perlsub manpage or the attributes manpage).

Ambiguous use of %s resolved as %s

(W ambiguous)(S) You said something that may not be interpreted the way you thought. Normally it's pretty easy to disambiguate it by supplying a missing quote, operator, parenthesis pair or declaration.

'|' and '<' may not both be specified on command line

(F) An error peculiar to VMS. Perl does its own command line redirection, and found that STDIN was a pipe, and that you also tried to redirect STDIN using '<'. Only one STDIN stream to a customer, please.

'|' and '>' may not both be specified on command line

(F) An error peculiar to VMS. Perl does its own command line redirection, and thinks you tried to redirect stdout both to a file and into a pipe to another command. You need to choose one or the other, though nothing's stopping you from piping into a program or Perl script which 'splits' output into two streams, such as

    open(OUT,">$ARGV[0]") or die "Can't write to $ARGV[0]: $!";
    while (<STDIN>) {
        print;
        print OUT;
    }
    close OUT;

Applying %s to %s will act on scalar(%s)

(W misc) The pattern match (//), substitution (s///), and transliteration (tr///) operators work on scalar values. If you apply one of them to an array or a hash, it will convert the array or hash to a scalar value -- the length of an array, or the population info of a hash -- and then work on that scalar value. This is probably not what you meant to do. See grep in the perlfunc manpage and map in the perlfunc manpage for alternatives.

Args must match #! line

(F) The setuid emulator requires that the arguments Perl was invoked with match the arguments specified on the #! line. Since some systems impose a one-argument limit on the #! line, try combining switches; for example, turn -w -U into -wU.

Arg too short for msgsnd

(F) msgsnd() requires a string at least as long as sizeof(long).

%s argument is not a HASH or ARRAY element

(F) The argument to exists() must be a hash or array element, such as:

    $foo{$bar}
    $ref->{"susie"}[12]

%s argument is not a HASH or ARRAY element or slice

(F) The argument to delete() must be either a hash or array element, such as:

    $foo{$bar}
    $ref->{"susie"}[12]

or a hash or array slice, such as:

    @foo[$bar, $baz, $xyzzy]
    @{$ref->[12]}{"susie", "queue"}

%s argument is not a subroutine name

(F) The argument to exists() for exists &sub must be a subroutine name, and not a subroutine call. exists &sub() will generate this error.

Argument ``%s'' isn't numeric%s

(W numeric) The indicated string was fed as an argument to an operator that expected a numeric value instead. If you're fortunate the message will identify which operator was so unfortunate.

Array @%s missing the @ in argument %d of %s()

(D deprecated) Really old Perl let you omit the @ on array names in some spots. This is now heavily deprecated.

assertion botched: %s

(P) The malloc package that comes with Perl had an internal failure.

Assertion failed: file ``%s''

(P) A general assertion failed. The file in question must be examined.

Assignment to both a list and a scalar

(F) If you assign to a conditional operator, the 2nd and 3rd arguments must either both be scalars or both be lists. Otherwise Perl won't know which context to supply to the right side.

Negative offset to vec in lvalue context

(F) When vec is called in an lvalue context, the second argument must be greater than or equal to zero.

Attempt to free non-arena SV: 0x%lx

(P internal) All SV objects are supposed to be allocated from arenas that will be garbage collected on exit. An SV was discovered to be outside any of those arenas.

Attempt to free nonexistent shared string

(P internal) Perl maintains a reference counted internal table of strings to optimize the storage and access of hash keys and other strings. This indicates someone tried to decrement the reference count of a string that can no longer be found in the table.

Attempt to free temp prematurely

(W debugging) Mortalized values are supposed to be freed by the free_tmps() routine. This indicates that something else is freeing the SV before the free_tmps() routine gets a chance, which means that the free_tmps() routine will be freeing an unreferenced scalar when it does try to free it.

Attempt to free unreferenced glob pointers

(P internal) The reference counts got screwed up on symbol aliases.

Attempt to free unreferenced scalar

(W internal) Perl went to decrement the reference count of a scalar to see if it would go to 0, and discovered that it had already gone to 0 earlier, and should have been freed, and in fact, probably was freed. This could indicate that SvREFCNT_dec() was called too many times, or that 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.

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.

Attempt to pack pointer to temporary value

(W pack) You tried to pass a temporary value (like the result of a function, or a computed expression) to the ``p'' pack() template. This means the result contains a pointer to a location that could become invalid anytime, even before the end of the current statement. Use literals or global values as arguments to the ``p'' pack() template to avoid this warning.

Attempt to use reference as lvalue in substr

(W substr) You supplied a reference as the first argument to substr() used as an lvalue, which is pretty strange. Perhaps you forgot to dereference it first. See substr in the perlfunc manpage.

Bad arg length for %s, is %d, should be %d

(F) You passed a buffer of the wrong size to one of msgctl(), semctl() or shmctl(). In C parlance, the correct sizes are, respectively, sizeof(struct msqid_ds *), sizeof(struct semid_ds *), and sizeof(struct shmid_ds *).

Bad evalled substitution pattern

(F) You've used the /e switch to evaluate the replacement for a substitution, but perl found a syntax error in the code to evaluate, most likely an unexpected right brace '}'.

Bad filehandle: %s

(F) A symbol was passed to something wanting a filehandle, but the symbol has no filehandle associated with it. Perhaps you didn't do an open(), or did it in another package.

Bad free() ignored

(S malloc) An internal routine called free() on something that had never been malloc()ed in the first place. Mandatory, but can be disabled by setting environment variable PERL_BADFREE to 0.

This message can be seen quite often with DB_File on systems with ``hard'' dynamic linking, like AIX and OS/2. It is a bug of Berkeley DB which is left unnoticed if DB uses forgiving system malloc().

Bad hash

(P) One of the internal hash routines was passed a null HV pointer.

Bad index while coercing array into hash

(F) The index looked up in the hash found as the 0'th element of a pseudo-hash is not legal. Index values must be at 1 or greater. See the perlref manpage.

Badly placed ()'s

(A) You've accidentally run your script through csh instead of Perl. Check the #! line, or manually feed your script into Perl yourself.

Bad name after %s::

(F) You started to name a symbol by using a package prefix, and then didn't finish the symbol. In particular, you can't interpolate outside of quotes, so

    $var = 'myvar';
    $sym = mypack::$var;

is not the same as

    $var = 'myvar';
    $sym = "mypack::$var";

Bad realloc() ignored

(S malloc) An internal routine called realloc() on something that had never been malloc()ed in the first place. Mandatory, but can be disabled by setting environment variable PERL_BADFREE to 1.

Bad symbol for array

(P) An internal request asked to add an array entry to something that wasn't a symbol table entry.

Bad symbol for filehandle

(P) An internal request asked to add a filehandle entry to something that wasn't a symbol table entry.

Bad symbol for hash

(P) An internal request asked to add a hash entry to something that wasn't a symbol table entry.

Bareword found in conditional

(W bareword) The compiler found a bareword where it expected a conditional, which often indicates that an || or && was parsed as part of the last argument of the previous construct, for example:

    open FOO || die;

It may also indicate a misspelled constant that has been interpreted as a bareword:

    use constant TYPO => 1;
    if (TYOP) { print "foo" }

The strict pragma is useful in avoiding such errors.

Bareword ``%s'' not allowed while ``strict subs'' in use

(F) With ``strict subs'' in use, a bareword is only allowed as a subroutine identifier, in curly brackets or to the left of the ``=>'' symbol. Perhaps you need to predeclare a subroutine?

Bareword ``%s'' refers to nonexistent package

(W bareword) You used a qualified bareword of the form Foo::, but the compiler saw no other uses of that namespace before that point. Perhaps you need to predeclare a package?

BEGIN failed--compilation aborted

(F) An untrapped exception was raised while executing a BEGIN subroutine. Compilation stops immediately and the interpreter is exited.

BEGIN not safe after errors--compilation aborted

(F) Perl found a BEGIN {} subroutine (or a use directive, which implies a BEGIN {}) after one or more compilation errors had already occurred. Since the intended environment for the BEGIN {} could not be guaranteed (due to the errors), and since subsequent code likely depends on its correct operation, Perl just gave up.

\1 better written as $1

(W syntax) Outside of patterns, backreferences live on as variables. The use of backslashes is grandfathered on the right-hand side of a substitution, but stylistically it's better to use the variable form because other Perl programmers will expect it, and it works better if there are more than 9 backreferences.

Binary number > 0b11111111111111111111111111111111 non-portable

(W portable) The binary number you specified is larger than 2**32-1 (4294967295) and therefore non-portable between systems. See the perlport manpage for more on portability concerns.

bind() on closed socket %s

(W closed) You tried to do a bind on a closed socket. Did you forget to check the return value of your socket() call? See bind in the perlfunc manpage.

Bit vector size > 32 non-portable

(W portable) Using bit vector sizes larger than 32 is non-portable.

Bizarre copy of %s in %s

(P) Perl detected an attempt to copy an internal value that is not copyable.

-P not allowed for setuid/setgid script

(F) The script would have to be opened by the C preprocessor by name, which provides a race condition that breaks security.

Buffer overflow in prime_env_iter: %s

(W internal) 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.

Callback called exit

(F) A subroutine invoked from an external package via call_sv() exited by calling exit.

%s() called too early to check prototype

(W prototype) 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 the perlsub manpage.

/ 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 pack in the perlfunc manpage.

Can't bless non-reference value

(F) Only hard references may be blessed. This is how Perl ``enforces'' encapsulation of objects. See the perlobj manpage.

Can't call method ``%s'' in empty package ``%s''

(F) You called a method correctly, and it correctly indicated a package functioning as a class, but that package doesn't have ANYTHING defined in it, let alone methods. See the perlobj manpage.

Can't call method ``%s'' on an undefined value

(F) You used the syntax of a method call, but the slot filled by the object reference or package name contains an undefined value. Something like this will reproduce the error:

    $BADREF = undef;
    process $BADREF 1,2,3;
    $BADREF->process(1,2,3);

Can't call method ``%s'' on unblessed reference

(F) A method call must know in what package it's supposed to run. It ordinarily finds this out from the object reference you supply, but you didn't supply an object reference in this case. A reference isn't an object reference until it has been blessed. See the perlobj manpage.

Can't call method ``%s'' without a package or object reference

(F) You used the syntax of a method call, but the slot filled by the object reference or package name contains an expression that returns a defined value which is neither an object reference nor a package name. Something like this will reproduce the error:

    $BADREF = 42;
    process $BADREF 1,2,3;
    $BADREF->process(1,2,3);

Can't chdir to %s

(F) You called perl -x/foo/bar, but /foo/bar is not a directory that you can chdir to, possibly because it doesn't exist.

Can't check filesystem of script ``%s'' for nosuid

(P) For some reason you can't check the filesystem of the script for nosuid.

Can't coerce array into hash

(F) You used an array where a hash was expected, but the array has no information on how to map from keys to array indices. You can do that only with arrays that have a hash reference at index 0.

Can't coerce %s to integer in %s

(F) Certain types of SVs, in particular real symbol table entries (typeglobs), can't be forced to stop being what they are. So you can't say things like:

    *foo += 1;

You CAN say

    $foo = *foo;
    $foo += 1;

but then $foo no longer contains a glob.

Can't coerce %s to number in %s

(F) Certain types of SVs, in particular real symbol table entries (typeglobs), can't be forced to stop being what they are.

Can't coerce %s to string in %s

(F) Certain types of SVs, in particular real symbol table entries (typeglobs), can't be forced to stop being what they are.

Can't create pipe mailbox

(P) An error peculiar to VMS. The process is suffering from exhausted quotas or other plumbing problems.

Can't declare class for non-scalar %s in ``%s''

(S) Currently, only scalar variables can declared with a specific class qualifier in a ``my'' or ``our'' declaration. The semantics may be extended for other types of variables in future.

Can't declare %s in ``%s''

(F) Only scalar, array, and hash variables may be declared as ``my'' or ``our'' variables. They must have ordinary identifiers as names.

Can't do inplace edit: %s is not a regular file

(S inplace) You tried to use the -i switch on a special file, such as a file in /dev, or a FIFO. The file was ignored.

Can't do inplace edit on %s: %s

(S inplace) The creation of the new file failed for the indicated reason.

Can't do inplace edit without backup

(F) You're on a system such as MS-DOS that gets confused if you try reading from a deleted (but still opened) file. You have to say -i.bak, or some such.

Can't do inplace edit: %s would not be unique

(S inplace) Your filesystem does not support filenames longer than 14 characters and Perl was unable to create a unique filename during inplace editing with the -i switch. The file was ignored.

Can't do {n,m} with n > m before << HERE in regex m/%s/

(F) Minima must be less than or equal to maxima. If you really want your regexp to match something 0 times, just put {0}. The << HERE shows in the regular expression about where the problem was discovered. See the perlre manpage.

Can't do setegid!

(P) The setegid() call failed for some reason in the setuid emulator of suidperl.

Can't do seteuid!

(P) The setuid emulator of suidperl failed for some reason.

Can't do setuid

(F) This typically means that ordinary perl tried to exec suidperl to do setuid emulation, but couldn't exec it. It looks for a name of the form sperl5.000 in the same directory that the perl executable resides under the name perl5.000, typically /usr/local/bin on Unix machines. If the file is there, check the execute permissions. If it isn't, ask your sysadmin why he and/or she removed it.

Can't do waitpid with flags

(F) This machine doesn't have either waitpid() or wait4(), so only waitpid() without flags is emulated.

Can't emulate -%s on #! line

(F) The #! line specifies a switch that doesn't make sense at this point. For example, it'd be kind of silly to put a -x on the #! line.

Can't exec ``%s'': %s

(W exec) An system(), exec(), or piped open call could not execute the named program for the indicated reason. Typical reasons include: the permissions were wrong on the file, the file wasn't found in $ENV{PATH}, the executable in question was compiled for another architecture, or the #! line in a script points to an interpreter that can't be run for similar reasons. (Or maybe your system doesn't support #! at all.)

Can't exec %s

(F) Perl was trying to execute the indicated program for you because that's what the #! line said. If that's not what you wanted, you may need to mention ``perl'' on the #! line somewhere.

Can't execute %s

(F) You used the -S switch, but the copies of the script to execute found in the PATH did not have correct permissions.

Can't find an opnumber for ``%s''

(F) A string of a form CORE::word was given to prototype(), but there is no builtin with the name word.

Can't find label %s

(F) You said to goto a label that isn't mentioned anywhere that it's possible for us to go to. See goto in the perlfunc manpage.

Can't find %s on PATH

(F) You used the -S switch, but the script to execute could not be found in the PATH.

Can't find %s on PATH, '.' not in PATH

(F) You used the -S switch, but the script to execute could not be found in the PATH, or at least not with the correct permissions. The script exists in the current directory, but PATH prohibits running it.

Can't find string terminator %s anywhere before EOF

(F) Perl strings can stretch over multiple lines. This message means that the closing delimiter was omitted. Because bracketed quotes count nesting levels, the following is missing its final parenthesis:

    print q(The character '(' starts a side comment.);

If you're getting this error from a here-document, you may have included unseen whitespace before or after your closing tag. A good programmer's editor will have a way to help you find these characters.

Can't find %s property definition %s

(F) You may have tried to use \p which means a Unicode property for example \p{Lu} is all uppercase letters. Escape the \p, either \\p (just the \p) or by \Q\p (the rest of the string, until possible \E).

Can't fork

(F) A fatal error occurred while trying to fork while opening a pipeline.

Can't get filespec - stale stat buffer?

(S) A warning peculiar to VMS. This arises because of the difference between access checks under VMS and under the Unix model Perl assumes. Under VMS, access checks are done by filename, rather than by bits in the stat buffer, so that ACLs and other protections can be taken into account. Unfortunately, Perl assumes that the stat buffer contains all the necessary information, and passes it, instead of the filespec, to the access checking routine. It will try to retrieve the filespec using the device name and FID present in the stat buffer, but this works only if you haven't made a subsequent call to the CRTL stat() routine, because the device name is overwritten with each call. If this warning appears, the name lookup failed, and the access checking routine gave up and returned FALSE, just to be conservative. (Note: The access checking routine knows about the Perl stat operator and file tests, so you shouldn't ever see this warning in response to a Perl command; it arises only if some internal code takes stat buffers lightly.)

Can't get pipe mailbox device name

(P) An error peculiar to VMS. After creating a mailbox to act as a pipe, Perl can't retrieve its name for later use.

Can't get SYSGEN parameter value for MAXBUF

(P) An error peculiar to VMS. Perl asked $GETSYI how big you want your mailbox buffers to be, and didn't get an answer.

Can't ``goto'' into the middle of a foreach loop

(F) A ``goto'' statement was executed to jump into the middle of a foreach loop. You can't get there from here. See goto in the perlfunc manpage.

Can't ``goto'' out of a pseudo block

(F) A ``goto'' statement was executed to jump out of what might look like a block, except that it isn't a proper block. This usually occurs if you tried to jump out of a sort() block or subroutine, which is a no-no. See goto in the perlfunc manpage.

Can't goto subroutine from an eval-string

(F) The ``goto subroutine'' call can't be used to jump out of an eval ``string''. (You can use it to jump out of an eval {BLOCK}, but you probably don't want to.)

Can't goto subroutine outside a subroutine

(F) The deeply magical ``goto subroutine'' call can only replace one subroutine call for another. It can't manufacture one out of whole cloth. In general you should be calling it out of only an AUTOLOAD routine anyway. See goto in the perlfunc manpage.

Can't ignore signal CHLD, forcing to default

(W signal) Perl has detected that it is being run with the SIGCHLD signal (sometimes known as SIGCLD) disabled. Since disabling this signal will interfere with proper determination of exit status of child processes, Perl has reset the signal to its default value. This situation typically indicates that the parent program under which Perl may be running (e.g. cron) is being very careless.

Can't ``last'' outside a loop block

(F) A ``last'' statement was executed to break out of the current block, except that there's this itty bitty problem called there isn't a current block. Note that an ``if'' or ``else'' block doesn't count as a ``loopish'' block, as doesn't a block given to sort(), map() or grep(). You can usually double the curlies to get the same effect though, because the inner curlies will be considered a block that loops once. See last in the perlfunc manpage.

Can't localize lexical variable %s

(F) You used local on a variable name that was previously declared as a lexical variable using ``my''. This is not allowed. If you want to localize a package variable of the same name, qualify it with the package name.

Can't localize pseudo-hash element

(F) You said something like local $ar->{'key'}, where $ar is a reference to a pseudo-hash. That hasn't been implemented yet, but you can get a similar effect by localizing the corresponding array element directly -- local $ar->[$ar->[0]{'key'}].

Can't localize through a reference

(F) You said something like local $$ref, which Perl can't currently handle, because when it goes to restore the old value of whatever $ref pointed to after the scope of the local() is finished, it can't be sure that $ref will still be a reference.

Can't locate %s

(F) You said to do (or require, or use) a file that couldn't be found. Perl looks for the file in all the locations mentioned in @INC, unless the file name included the full path to the file. Perhaps you need to set the PERL5LIB or PERL5OPT environment variable to say where the extra library is, or maybe the script needs to add the library name to @INC. Or maybe you just misspelled the name of the file. See require in the perlfunc manpage and the lib manpage.

Can't locate auto/%s.al in @INC

(F) A function (or method) was called in a package which allows autoload, but there is no function to autoload. Most probable causes are a misprint in a function/method name or a failure to AutoSplit the file, say, by doing make install.

Can't locate object method ``%s'' via package ``%s''

(F) You called a method correctly, and it correctly indicated a package functioning as a class, but that package doesn't define that particular method, nor does any of its base classes. See the perlobj manpage.

(perhaps you forgot to load ``%s''?)

(F) This is an educated guess made in conjunction with the message ``Can't locate object method \''%s\`` via package \''%s\``''. It often means that a method requires a package that has not been loaded.

Can't locate package %s for @%s::ISA

(W syntax) The @ISA array contained the name of another package that doesn't seem to exist.

Can't make list assignment to \%ENV on this system

(F) List assignment to %ENV is not supported on some systems, notably VMS.

Can't modify %s in %s

(F) You aren't allowed to assign to the item indicated, or otherwise try to change it, such as with an auto-increment.

Can't modify nonexistent substring

(P) The internal routine that does assignment to a substr() was handed a NULL.

Can't modify non-lvalue subroutine call

(F) Subroutines meant to be used in lvalue context should be declared as such, see Lvalue subroutines in the perlsub manpage.

Can't msgrcv to read-only var

(F) The target of a msgrcv must be modifiable to be used as a receive buffer.

Can't ``next'' outside a loop block

(F) A ``next'' statement was executed to reiterate the current block, but there isn't a current block. Note that an ``if'' or ``else'' block doesn't count as a ``loopish'' block, as doesn't a block given to sort(), map() or grep(). You can usually double the curlies to get the same effect though, because the inner curlies will be considered a block that loops once. See next in the perlfunc manpage.

Can't open %s: %s

(S inplace) The implicit opening of a file through use of the <> filehandle, either implicitly under the -n or -p command-line switches, or explicitly, failed for the indicated reason. Usually this is because you don't have read permission for a file which you named on the command line.

Can't open bidirectional pipe

(W pipe) You tried to say open(CMD, "|cmd|"), which is not supported. You can try any of several modules in the Perl library to do this, such as IPC::Open2. Alternately, direct the pipe's output to a file using ``>'', and then read it in under a different file handle.

Can't open error file %s as stderr

(F) An error peculiar to VMS. Perl does its own command line redirection, and couldn't open the file specified after '2>' or '2>>' on the command line for writing.

Can't open input file %s as stdin

(F) An error peculiar to VMS. Perl does its own command line redirection, and couldn't open the file specified after '<' on the command line for reading.

Can't open output file %s as stdout

(F) An error peculiar to VMS. Perl does its own command line redirection, and couldn't open the file specified after '>' or '>>' on the command line for writing.

Can't open output pipe (name: %s)

(P) An error peculiar to VMS. Perl does its own command line redirection, and couldn't open the pipe into which to send data destined for stdout.

Can't open perl script ``%s'': %s

(F) The script you specified can't be opened for the indicated reason.

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 PERL_ENV_TABLES (see the perlvms manpage) so that environ is not searched.

Can't redefine active sort subroutine %s

(F) Perl optimizes the internal handling of sort subroutines and keeps pointers into them. You tried to redefine one such sort subroutine when it was currently active, which is not allowed. If you really want to do this, you should write sort { &func } @x instead of sort func @x.

Can't ``redo'' outside a loop block

(F) A ``redo'' statement was executed to restart the current block, but there isn't a current block. Note that an ``if'' or ``else'' block doesn't count as a ``loopish'' block, as doesn't a block given to sort(), map() or grep(). You can usually double the curlies to get the same effect though, because the inner curlies will be considered a block that loops once. See redo in the perlfunc manpage.

Can't remove %s: %s, skipping file

(S inplace) 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.

Can't rename %s to %s: %s, skipping file

(S inplace) The rename done by the -i switch failed for some reason, probably because you don't have write permission to the directory.

Can't reopen input pipe (name: %s) in binary mode

(P) An error peculiar to VMS. Perl thought stdin was a pipe, and tried to reopen it to accept binary data. Alas, it failed.

Can't resolve method `%s' overloading `%s' in package `%s'

(F|P) Error resolving overloading specified by a method name (as opposed to a subroutine reference): no such method callable via the package. If method name is ???, this is an internal error.

Can't reswap uid and euid

(P) The setreuid() call failed for some reason in the setuid emulator of suidperl.

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.

Can't return %s to lvalue scalar context

(F) You tried to return a complete array or hash from an lvalue subroutine, but you called the subroutine in a way that made Perl think you meant to return only one value. You probably meant to write parentheses around the call to the subroutine, which tell Perl that the call should be in list context.

Can't return outside a subroutine

(F) The return statement was executed in mainline code, that is, where there was no subroutine call to return out of. See the perlsub manpage.

Can't stat script ``%s''

(P) For some reason you can't fstat() the script even though you have it open already. Bizarre.

Can't swap uid and euid

(P) The setreuid() call failed for some reason in the setuid emulator of suidperl.

Can't take log of %g

(F) For ordinary real numbers, you can't take the logarithm of a negative number or zero. There's a Math::Complex package that comes standard with Perl, though, if you really want to do that for the negative numbers.

Can't take sqrt of %g

(F) For ordinary real numbers, you can't take th