NAME
printf - formatted output

SYNOPSIS
printf format [ arguments ... ]

DESCRIPTION
Printf formats and prints its arguments, after the first, under
control of the format. The format is a character string which
contains three types of objects: plain characters, which are simply
copied to standard output, character escape sequences which are
converted and copied to the standard output, and format
specifications, each of which causes printing of the next
successive argument.

The arguments after the first are treated as strings if the
corresponding format is either c or s; otherwise it is evaluated as
a C constant, with the following extensions:
A leading plus or minus sign is allowed.
If the leading character is a single or double quote, or not a
digit, plus, or minus sign, the value is the ASCII code of the
next character.

The format string is reused as often as necessary to satisfy the
arguments. Any extra format specifications are evaluated with zero
or the null string.

Character escape sequences are in backslash notation as defined in
the draft proposed ANSI C Standard X3J11. The characters and their
meanings are as follows:

Write a <bell> character.

Write a <backspace> character.

Write a <form-feed> character.

Write a <new-line> character.

Write a <carriage return> character.

Write a <tab> character.

Write a <vertical tab> character.

´ Write a <single quote> character.

\ Write a backslash character.

0m Write an 8-bit character whose ASCII value is the 1-, 2-, or
3-digit octal number num.

Each format specification is introduced by the percent character
("%"). The remainder of the format specification includes, in
the following order:

Zero or more of the following flags:

a ‘#’ character specifying that the value should be printed
in an "alternate form". For c, d, and s, formats, this
option has no effect. For the o formats the precision of the
number is increased to force the first character of the
output string to a zero. For the x(X) format, a non-zero
result has the string 0x(0X) prepended to it. For e, E, f,
g, and G, formats, the result will always contain a decimal
point, even if no digits follow the point (normally, a
decimal point only appears in the results of those formats if
a digit follows the decimal point). For g and G formats,
trailing zeros are not removed from the result as they would
otherwise be;

a minus sign ‘-’ which specifies left adjustment of the
output in the indicated field;

a ‘+’ character specifying that there should always be a sign
placed before the number when using signed formats.

a space specifying that a blank should be left before a
positive number for a signed format. A ‘+’ overrides a space
if both are used;

a zero ‘0’ character indicating that zero-padding should be
used rather than blank-padding. A ‘-’ overrides a ‘0’ if
both are used;

an optional digit string specifying a field width; if the output
string has fewer characters than the field width it will be
blank-padded on the left (or right, if the left-adjustment
indicator has been given) to make up the field width (note that
a leading zero is a flag, but an embedded zero is part of a
field width);

an optional period, followed by an optional digit string giving
a precision which specifies the number of digits to appear after
the decimal point, for e- and f-formats, or the maximum number
of characters to be printed from a string; if the digit string
is missing, the precision is treated as zero;

a character which indicates the type of format to use.

A field width or precision may be ‘*’ instead of a digit string.
In this case an argument supplies the field width or precision.

The format characters and their meanings are:

diouXx
The argument is printed as a signed decimal (d or i), unsigned
decimal, unsigned octal, or unsigned hexadecimal (X or x),
respectively.

f The argument is printed in the style ‘[-]ddd.ddd’ where the
number of d’s after the decimal point is equal to the
precision specification for the argument. If the precision is
missing, 6 digits are given; if the precision is explicitly 0,
no digits and no decimal point are printed.

eE The argument is printed in the style ‘[-]d.ddde_dd’ where
there is one digit before the decimal point and the number
after is equal to the precision specification for the
argument; when the precision is missing, 6 digits are
produced. An upper-case E is used for an ‘E’ format.

gG The argument is printed in style f or in style e (E) whichever
gives full precision in minimum space.

c The first character of argument is printed.

s Characters from the string argument are printed until the end
is reached or until the number of characters indicated by the
precision specification is reached; however if the precision
is 0 or missing, all characters in the string are printed.

% Print a ‘%’; no argument is used.

In no case does a non-existent or small field width cause
truncation of a field; padding takes place only if the specified
field width exceeds the actual width.

RETURN VALUE
Printf exits 0 on success, 1 on failure.