How can I compute the range of signed and unsigned types

[beowulf at hoolan.org]

The most effective method I use frequently:

% gdb
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This GDB was configured as "i386-redhat-linux".
(gdb) p sizeof(char)
$1 = 1
(gdb) p sizeof(int)
$2 = 4
(gdb) p sizeof(long)
$3 = 4
(gdb) p sizeof(long long)
$4 = 8
(gdb) p sizeof(float)
$5 = 4
(gdb) p sizeof(double)
$6 = 8
(gdb) p sizeof(long double)
$7 = 10