Parameters for Message Win32 API Calls (Windows)

dwFlags
dwFlags specifies options to the formatting process along with how to interpret the lpSource parameter. The low order 16 bits of this parameter are the maximum width of the line, in characters. Possible values are:
 
FORMAT_MESSAGE_ALLOCATE_BUFFER
lpBuffer is a PVOID* and nSize is the minimum size to allocate. This function will then allocate a buffer large enough to hold the formatted message and store the pointer to the buffer in the location pointed to by lpBuffer. The caller should free the buffer with LocalFree when they are done using it.
 
FORMAT_MESSAGE_IGNORE_INSERTS
Insert sequences in the message definition will be ignored and passed through to the output buffer, as is. This is useful for fetching a message for later formatting. If this flag is set, the lpArgument parameter is ignored.
 
FORMAT_MESSAGE_FROM_STRING
lpSource is a pointer to a null terminated message definition. It can contain insert sequences, just as the message text in the .mc file can.
 
FORMAT_MESSAGE_FROM_HMODULE
lpSource is a module handle that contains the message table resource(s) to search. If this handle is NULL, then the current process' application image file will be searched.
 
FORMAT_MESSAGE_FROM_SYSTEM
If the requested message was not found in lpSource, or if lpSource was not examined (i.e. neither of the preceding function will search the system message table resource(s).
 
FORMAT_MESSAGE_ARGUMENT_ARRAY
If set, this parameter specifies that the passed Arguments parameter is NOT a va_list structure, but instead is just a point to an array of 32-bit values that represent the arguments.
 
FORMAT_MESSAGE_MAX_WIDTH_MAX
The low order 8 bits specify the maximum width of each line formatted into the output buffer. A maximum width of zero means that no restrictions are placed on the width, and only the line breaks in the message definition will be placed in the output buffer. If a non-zero value is specified, then line breaks in the message definition text are ignored, and instead line breaks are calculated based on the maximum width, with white space delimited strings never being split across a line break. Hard coded breaks in the message definition text, that are identified by the %n escape sequence, are always output to the output buffer.
 
If the width specified is FORMAT_MESSAGE_MESSAGE_MAX_WIDTH_MASK, then line breaks in the message file are ignored and only hard coded line breaks are kept. None are generated.
 
lpSource
Specifies where to retrieve the message definition from. The type of this parameter depends upon the settings in the dwFlags parameter.
 
FORMAT_MESSAGE_FROM_HMODULE - lpSource is an hModule of the module that contains the message table to search.
 
FORMAT_MESSAGE_FROM_STRING - lpSource is an LPSTR that points to unformatted message tex. It will be scanned for inserts and formatted accordingly.
If neither of these options is specified, then this parameter is ignored.
 
dwMessageId
Specifies the 32-bit message identifier that identifies the message being requested. This parameter is ignored if the FORMAT_MESSAGE_FROM_STRING flag is specified.
 
dwLanguageId
Specifies the 32-bit message identifier that identifies the message being requested. This parameter is ignored if the FORMAT_MESSAGE_FROM_STRING flag is specified.
 
lpBuffer
Specifies a pointer to a buffer where the formatted message is to be written. A terminating null byte will also be written. IF the FORMAT_MESSAGE_ALLOCATE_BUFFER flag was specified, the this parameter points tot a 32-bit pointer value that is filled in by this call with a pointer allocated via LocalAlloc to contain the text of the message.
 
nSize
Specifies the maximum number of bytes that can be stored in the output buffer. This parameter is ignored if the FORMAT_MESSAGE_ALLOCATE_BUFFER flag is set.
 
Arguments
Specifies a pointer to a variable number of arguments. These arguments are used to satisfy insert requests in the format string. Thus, %1 in the format string specifies the first argument in the variable number of arguments described by the Arguments parameter; %3 would specify the third, and so on.
 
The interpretation of each 32-bit arguments value depends on the formatting infomration associated with the inset in the message definition. The default is to treat each pointer as a point to a null terminated string.
 
By default, the Arguments parameter is of type va_list, which is a language and implementation specific data type for describing a variable number of arguments. If you do not have a pointer of type va_list, then specify the FORMAT_MESSAGE_ARGUMENT_ARRAY flag and pass a pointer to an array of 32-bit values that are input to the message formatted as the insert values.



Message Compiler - An Overview
Message Compiler - Syntax
Message WinAPI Calls
MKMSGF - Make Message File Utility
MKMSGF - Syntax