25 Localization library [localization]

25.4 Standard locale categories [locale.categories]

25.4.5 The time category [category.time]

25.4.5.3 Class template time_­put [locale.time.put]

namespace std {
  template <class charT, class OutputIterator = ostreambuf_iterator<charT>>
    class time_put : public locale::facet {
    public:
      using char_type = charT;
      using iter_type = OutputIterator;

      explicit time_put(size_t refs = 0);

      // the following is implemented in terms of other member functions.
      iter_type put(iter_type s, ios_base& f, char_type fill, const tm* tmb,
                    const charT* pattern, const charT* pat_end) const;
      iter_type put(iter_type s, ios_base& f, char_type fill,
                    const tm* tmb, char format, char modifier = 0) const;

      static locale::id id;

    protected:
      ~time_put();
      virtual iter_type do_put(iter_type s, ios_base&, char_type, const tm* t,
                               char format, char modifier) const;
    };
}

25.4.5.3.1 time_­put members [locale.time.put.members]

iter_type put(iter_type s, ios_base& str, char_type fill, const tm* t, const charT* pattern, const charT* pat_end) const; iter_type put(iter_type s, ios_base& str, char_type fill, const tm* t, char format, char modifier = 0) const;
Effects: The first form steps through the sequence from pattern to pat_­end, identifying characters that are part of a format sequence.
Each character that is not part of a format sequence is written to s immediately, and each format sequence, as it is identified, results in a call to do_­put; thus, format elements and other characters are interleaved in the output in the order in which they appear in the pattern.
Format sequences are identified by converting each character c to a char value as if by ct.narrow(c, 0), where ct is a reference to ctype<charT> obtained from str.getloc().
The first character of each sequence is equal to '%', followed by an optional modifier character mod246 and a format specifier character spec as defined for the function strftime.
If no modifier character is present, mod is zero.
For each valid format sequence identified, calls do_­put(s, str, fill, t, spec, mod).
The second form calls do_­put(s, str, fill, t, format, modifier).
[Note
:
The fill argument may be used in the implementation-defined formats or by derivations.
A space character is a reasonable default for this argument.
end note
]
Returns: An iterator pointing immediately after the last character produced.
Although the C programming language defines no modifiers, most vendors do.

25.4.5.3.2 time_­put virtual functions [locale.time.put.virtuals]

iter_type do_put(iter_type s, ios_base&, char_type fill, const tm* t, char format, char modifier) const;
Effects: Formats the contents of the parameter t into characters placed on the output sequence s.
Formatting is controlled by the parameters format and modifier, interpreted identically as the format specifiers in the string argument to the standard library function strftime()247, except that the sequence of characters produced for those specifiers that are described as depending on the C locale are instead implementation-defined.248
Returns: An iterator pointing immediately after the last character produced.
[Note
:
The fill argument may be used in the implementation-defined formats or by derivations.
A space character is a reasonable default for this argument.
end note
]
Interpretation of the modifier argument is implementation-defined, but should follow POSIX conventions.
Implementations should refer to other standards such as POSIX for these definitions.