The string "A" isn't a number so none of the number or character expecting formats will do what you're apparently expecting (when converted to a number the numeric value is zero). Pass a number if you want to format a number (chr and/or ord will probably be of interest).

$ perl -E '$x = ord(q{A});printf( join( qq{\t}, qw( %c %x %d ) ) . qq{
+\n}, ($x)x3 )'
A       41      65
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Perl is not C. Though I occasionally use sprintf in Perl, I rarely use printf, whose doco warns:

Don't fall into the trap of using a printf when a simple print would do. The print is more efficient and less error prone.

Hope the following test program clarifies:

use strict;
use warnings;

my $ca = 'A';
print "$ca\n";              # outputs A
printf "%s\n", $ca;         # outputs A
printf "%c\n", ord($ca);    # outputs A
printf "%x\n", ord($ca);    # outputs 41
printf "%d\n", ord($ca);    # outputs 65
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See also: ord, chr, hex, oct, sprintf

Thanks. That clears it up nicely. I read the bit about not using printf when print will do, but I did not know to look for ord. I was hoping that by specifying $ca with single quotes, instead of double quotes Perl would not treat $ca as a string. As the other reply hinted, I have been doing C recently, and Perl is not C. Thanks again. pgmer6809

'A' produces a string. The same string as "A".

The formats largely control how numbers are converted to strings for printing. Strings are already strings, so only one format is needed for them (%s).

%c applies chr to a number, %x produces a hex representation of a number, and %d produces a decimal representation of a number.

You probably wanted to pass ord('A') aka 0x41 aka 65.