• 1Parameters
• 2Return value
• 3Notes
• 4Example
• 5References
• 6See also

Writes asingle character.

• The argument is first converted tounsignedchar.
• If thel modifier is used, the argument is first converted to a character string as if by%ls with awchar_t[2] argument.

Writes acharacter string.

• The argument must be a pointer to the initial element of an array of characters.
• Precision specifies the maximum number of bytes to be written. IfPrecision is not specified, writes every byte up to and not including the first null terminator.
• If thel specifier is used, the argument must be a pointer to the initial element of an array ofwchar_t, which is converted to char array as if by a call towcrtomb with zero-initialized conversion state.

Converts asigned integer into decimal representation[-]dddd.

• Precision specifies the minimum number of digits to appear. The default precision is1.
• If both the converted value and the precision are​0​ the conversion results in no characters.
• For thez modifier, the expected argument type is the signed version ofsize_t.

Converts anunsigned integer into octal representationoooo.

• Precision specifies the minimum number of digits to appear. The default precision is1.
• If both the converted value and the precision are​0​ the conversion results in no characters.
• In thealternative implementation precision is increased if necessary, to write one leading zero. In that case if both the converted value and the precision are​0​, single​0​ is written.

Converts anunsigned integer into hexadecimal representationhhhh.

• For thex conversion lettersabcdef are used.
• For theX conversion lettersABCDEF are used.
• Precision specifies the minimum number of digits to appear. The default precision is1.
• If both the converted value and the precision are​0​ the conversion results in no characters.
• In thealternative implementation0x or0X is prefixed to results if the converted value is nonzero.

Converts anunsigned integer into decimal representationdddd.

• Precision specifies the minimum number of digits to appear.
• The default precision is1.
• If both the converted value and the precision are​0​ the conversion results in no characters.

Convertsfloating-point number to the decimal notation in the style[-]ddd.ddd.

• Precision specifies the exact number of digits to appear after the decimal point character.
• The default precision is6.
• In thealternative implementation decimal point character is written even if no digits follow it.
• For infinity and not-a-number conversion style seenotes.

Convertsfloating-point number to the decimal exponent notation.

• For thee conversion style[-]d.ddd e±dd is used.
• For theE conversion style[-]d.ddd E±dd is used.
• The exponent contains at least two digits, more digits are used only if necessary.
• If the value is​0​, the exponent is also​0​.
• Precision specifies the exact number of digits to appear after the decimal point character.
• The default precision is6.
• In thealternative implementation decimal point character is written even if no digits follow it.
• For infinity and not-a-number conversion style seenotes.

Convertsfloating-point number to the hexadecimal exponent notation.

• For thea conversion style[-] 0xh.hhh p±d is used.
• For theA conversion style[-] 0Xh.hhh P±d is used.
• The first hexadecimal digit is not0 if the argument is a normalized floating-point value.
• If the value is​0​, the exponent is also​0​.
• Precision specifies the exact number of digits to appear after the hexadecimal point character.
• The default precision is sufficient for exact representation of the value.
• In thealternative implementation decimal point character is written even if no digits follow it.
• For infinity and not-a-number conversion style seenotes.

Convertsfloating-point number to decimal or decimal exponent notation depending on the value and theprecision.

• For theg conversion style conversion with stylee orf will be performed.
• For theG conversion style conversion with styleE orf(until C99)F(since C99) will be performed.
• LetP equal the precision if nonzero,6 if the precision is not specified, or1 if the precision is​0​. Then, if a conversion with styleE would have an exponent ofX:
  • IfP > X ≥ −4, the conversion is with stylef orF(since C99) and precisionP − 1 − X.
  • Otherwise, the conversion is with stylee orE and precisionP − 1.
• Unlessalternative representation is requested the trailing zeros are removed, also the decimal point character is removed if no fractional part is left.
• For infinity and not-a-number conversion style seenotes.

Returns thenumber of characters written so far by this call to the function.

• The result iswritten to the value pointed to by the argument.
• The specification may not contain anyflag,field width, orprecision.
• For thez modifier, the expected argument type isS*, whereS is the signed version ofsize_t.

Writes an implementation defined character sequence defining apointer.

The floating-point conversion functions convert infinity toinf orinfinity. Which one is used is implementation defined.

Not-a-number is converted tonan ornan(char_sequence). Which one is used is implementation defined.

The conversionsF,E,G,A outputINF,INFINITY,NAN instead.

The conversion specifier used to printchar,unsignedchar,signedchar,short, andunsignedshort expects promoted types ofdefault argument promotions, but before printing its value will be converted tochar,unsignedchar,signedchar,short, andunsignedshort. It is safe to pass values of these types because of the promotion that takes place when a variadic function is called.

The correct conversion specifications for the fixed-width character types (int8_t, etc) are defined in the header<inttypes.h> (althoughPRIdMAX,PRIuMAX, etc is synonymous with%jd,%ju, etc).

The memory-writing conversion specifier%n is a common target of security exploits where format strings depend on user input and is not supported by the bounds-checkedprintf_s family of functions(since C11).

There is asequence point after the action of each conversion specifier; this permits storing multiple%n results in the same variable or, as an edge case, printing a string modified by an earlier%n within the same call.

If a conversion specification is invalid, the behavior is undefined.