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# dmd.chkformat

Check the arguments to printf and scanf against the format string.
Authors:
Walter Bright
License:
Boost License 1.0

Source chkformat.d

Documentation https://dlang.org/phobos/dmd_chkformat.html

Coverage https://codecov.io/gh/dlang/dmd/src/master/src/dmd/chkformat.d

bool `checkPrintfFormat`(ref const Loc `loc`, scope const char[] `format`, scope Expression[] `args`, bool `isVa_list`);
  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:
  1. incompatible sizes which will cause argument misalignment 2. deferencing arguments that are not pointers 3. insufficient number of arguments 4. struct arguments 5. array and slice arguments 6. non-pointer arguments to s specifier 7. non-standard formats 8. 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)

  Returns:
  true if errors occurred

  References C99 7.19.6.1 http://www.cplusplus.com/reference/cstdio/printf/

bool `checkScanfFormat`(ref const Loc `loc`, scope const char[] `format`, scope Expression[] `args`, bool `isVa_list`);
  Check that arguments to a scanf format string are compatible with that string. Issue errors for incompatibilities.
  Follows the C99 specification for scanf.
  Takes a generous, rather than strict, view of compatiblity. For example, an unsigned value can be formatted with a signed specifier.
  Diagnosed incompatibilities are:
  1. incompatible sizes which will cause argument misalignment 2. deferencing arguments that are not pointers 3. insufficient number of arguments 4. struct arguments 5. array and slice arguments 6. non-standard formats 7. 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)

  Returns:
  true if errors occurred

  References C99 7.19.6.2 http://www.cplusplus.com/reference/cstdio/scanf/

Copyright © 1999-2020 by the D Language Foundation | Page generated by Ddoc on Mon May 11 10:57:58 2020