Library Reference

version 2.112.0

Internal API

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dmd.chkformat

Check the arguments toprintf andscanf against theformat string.

Authors:

Walter Bright

License:

Boost License 1.0

Sourcechkformat.d

Documentationhttps://dlang.org/phobos/dmd_chkformat.html

Coveragehttps://codecov.io/gh/dlang/dmd/src/master/compiler/src/dmd/chkformat.d

boolcheckPrintfFormat(Locloc, scope const char[]format, scope Expression[]args, boolisVa_list, ErrorSinkeSink);

Check that arguments to a printf format string are compatible with that string. Issue errors for incompatibilities.

Follows the C99 specification for printf.

Takes a generous, rather than strict, view of compatiblity. For example, an unsigned value can be formatted with a signed specifier.

Diagnosed incompatibilities are:

incompatible sizes which will cause argument misalignment
deferencing arguments that are not pointers
insufficient number of arguments
struct arguments
array and slice arguments
non-pointer arguments tos specifier
non-standard formats
undefined behavior per C99

Per the C Standard, extra arguments are ignored.

No attempt is made to fix the arguments or the format string.

Parameters:

Loc`loc`	location for error messages
char[]`format`	format string
Expression[]`args`	arguments to match with format string
bool`isVa_list`	if a "v" function (format check only)
ErrorSink`eSink`	where the error messages go

Returns:

true if errors occurred

ReferencesC99 7.19.6.1https://www.cplusplus.com/reference/cstdio/printf/

boolcheckScanfFormat(Locloc, scope const char[]format, scope Expression[]args, boolisVa_list, ErrorSinkeSink);

Check that arguments to a scanf format string are compatible with that string. Issue errors for incompatibilities.

Follows the C99 specification for scanf.