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sprintf - formatted print into a string |
sprintf FORMAT, LIST
Returns a string formatted by the usual printf conventions of the C library function sprintf(). See the sprintf(3) manpage or the printf(3) manpage on your system for an explanation of the general principles.
Perl does all of its own sprintf() formatting -- it emulates the C function sprintf(), but it doesn’t use it (except for floating-point numbers, and even then only the standard modifiers are allowed). As a result, any non-standard extensions in your local sprintf() are not available from Perl.
Perl’s sprintf() permits the following universally-known conversions:
%% a percent
sign
%c a character with the given number
%s a string
%d a signed integer, in decimal
%u an unsigned integer, in decimal
%o an unsigned integer, in octal
%x an unsigned integer, in hexadecimal
%e a floating-point number, in scientific notation
%f a floating-point number, in fixed decimal notation
%g a floating-point number, in %e or %f notation
In addition, Perl permits the following widely-supported conversions:
%X like %x, but
using upper-case letters
%E like %e, but using an upper-case "E"
%G like %g, but with an upper-case "E" (if
applicable)
%p a pointer (outputs the Perl value’s address in
hexadecimal)
%n special: *stores* the number of characters output so far
into the next variable in the parameter list
Finally, for backward (and we do mean "backward") compatibility, Perl permits these unnecessary but widely-supported conversions:
%i a synonym
for %d
%D a synonym for %ld
%U a synonym for %lu
%O a synonym for %lo
%F a synonym for %f
Perl permits the following universally-known flags between the % and the conversion letter:
space prefix
positive number with a space
+ prefix positive number with a plus sign
- left-justify within the field
0 use zeros, not spaces, to right-justify
# prefix octal with "0", hex with "0x"
number minimum field width
.number "precision": digits after decimal point
for floating-point,
max length for string, minimum length for integer
l interpret integer as C type "long" or
"unsigned long"
h interpret integer as C type "short" or
"unsigned short"
There is also one Perl-specific flag:
V interpret integer as Perl’s standard integer type
Where a number would appear in the flags, an asterisk ("*") may be used instead, in which case Perl uses the next item in the parameter list as the given number (that is, as the field width or precision). If a field width obtained through "*" is negative, it has the same effect as the ’-’ flag: left-justification.
If use locale is in effect, the character used for the decimal point in formatted real numbers is affected by the LC_NUMERIC locale. See the perllocale manpage.