я не очень понял, какая у вас ОС.
Код: Выделить всё
PRINTF(3) Linux Programmer's Manual PRINTF(3)
NAME
printf, fprintf, sprintf, snprintf, vprintf, vfprintf, vsprintf,
vsnprintf - formatted output conversion
SYNOPSIS
#include <stdio.h>
int printf(const char *format, ...);
int fprintf(FILE *stream, const char *format, ...);
int sprintf(char *str, const char *format, ...);
int snprintf(char *str, size_t size, const char *format, ...);
#include <stdarg.h>
int vprintf(const char *format, va_list ap);
int vfprintf(FILE *stream, const char *format, va_list ap);
int vsprintf(char *str, const char *format, va_list ap);
int vsnprintf(char *str, size_t size, const char *format, va_list ap);
DESCRIPTION
The functions in the printf() family produce output according to a for‐
mat as described below. The functions printf() and vprintf() write out‐
put to stdout, the standard output stream; fprintf() and vfprintf()
write output to the given output stream; sprintf(), snprintf(),
vsprintf() and vsnprintf() write to the character string str.
The functions vprintf(), vfprintf(), vsprintf(), vsnprintf() are equiv‐
alent to the functions printf(), fprintf(), sprintf(), snprintf(),
respectively, except that they are called with a va_list instead of a
variable number of arguments. These functions do not call the va_end
macro. Consequently, the value of ap is undefined after the call. The
application should call va_end(ap) itself afterwards.
These eight functions write the output under the control of a format
string that specifies how subsequent arguments (or arguments accessed
via the variable-length argument facilities of stdarg(3)) are converted
for output.
Return value
Upon successful return, these functions return the number of characters
printed (not including the trailing '\' used to end output to
strings). The functions snprintf() and vsnprintf() do not write more
than size bytes (including the trailing '\'). If the output was trun‐
cated due to this limit then the return value is the number of charac‐
ters (not including the trailing '\') which would have been written to
the final string if enough space had been available. Thus, a return
value of size or more means that the output was truncated. (See also
below under NOTES.) If an output error is encountered, a negative
value is returned.
Format of the format string
The format string is a character string, beginning and ending in its
initial shift state, if any. The format string is composed of zero or
more directives: ordinary characters (not %), which are copied
unchanged to the output stream; and conversion specifications, each of
which results in fetching zero or more subsequent arguments. Each con‐
version specification is introduced by the character %, and ends with a
conversion specifier. In between there may be (in this order) zero or
more flags, an optional minimum field width, an optional precision and
an optional length modifier.
The arguments must correspond properly (after type promotion) with the
conversion specifier. By default, the arguments are used in the order
given, where each ‘*' and each conversion specifier asks for the next
argument (and it is an error if insufficiently many arguments are
given). One can also specify explicitly which argument is taken, at
each place where an argument is required, by writing ‘%m$' instead of
‘%' and ‘*m$' instead of ‘*', where the decimal integer m denotes the
position in the argument list of the desired argument, indexed starting
from 1. Thus,
printf("%*d", width, num);
and
printf("%2$*1$d", width, num);
are equivalent. The second style allows repeated references to the same
argument. The C99 standard does not include the style using ‘$', which
comes from the Single Unix Specification. If the style using ‘$' is
used, it must be used throughout for all conversions taking an argument
and all width and precision arguments, but it may be mixed with ‘%%'
formats which do not consume an argument. There may be no gaps in the
numbers of arguments specified using ‘$'; for example, if arguments 1
and 3 are specified, argument 2 must also be specified somewhere in the
format string.
For some numeric conversions a radix character (‘decimal point') or
thousands' grouping character is used. The actual character used
depends on the LC_NUMERIC part of the locale. The POSIX locale uses ‘.'
as radix character, and does not have a grouping character. Thus,
printf("%'.2f", 1234567.89);
results in ‘1234567.89' in the POSIX locale, in ‘1234567,89' in the
nl_NL locale, and in ‘1.234.567,89' in the da_DK locale.
The flag characters
The character % is followed by zero or more of the following flags:
# The value should be converted to an ‘‘alternate form''. For o
conversions, the first character of the output string is made
zero (by prefixing a 0 if it was not zero already). For x and X
conversions, a non-zero result has the string ‘0x' (or ‘0X' for
X conversions) prepended to it. For a, A, e, E, f, F, g, and G
conversions, the result will always contain a decimal point,
even if no digits follow it (normally, a decimal point appears
in the results of those conversions only if a digit follows).
не подскажете тогда, как установить man 3 printf, когда у меня в системе есть только 1?
