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authorIngo Molnar <mingo@elte.hu>2008-12-04 02:52:14 -0500
committerIngo Molnar <mingo@elte.hu>2008-12-04 02:52:14 -0500
commitcb9c34e6d090d376b77becaa5d29a65dec7f4272 (patch)
tree3678abce20d6825aebe3fec218057d4131e13fd6 /Documentation/printk-formats.txt
parent470c66239ef0336429b35345f3f615d47341e13b (diff)
parent061e41fdb5047b1fb161e89664057835935ca1d2 (diff)
Merge commit 'v2.6.28-rc7' into core/locking
Diffstat (limited to 'Documentation/printk-formats.txt')
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1If variable is of Type, use printk format specifier:
2---------------------------------------------------------
3 int %d or %x
4 unsigned int %u or %x
5 long %ld or %lx
6 unsigned long %lu or %lx
7 long long %lld or %llx
8 unsigned long long %llu or %llx
9 size_t %zu or %zx
10 ssize_t %zd or %zx
11
12Raw pointer value SHOULD be printed with %p.
13
14u64 SHOULD be printed with %llu/%llx, (unsigned long long):
15
16 printk("%llu", (unsigned long long)u64_var);
17
18s64 SHOULD be printed with %lld/%llx, (long long):
19
20 printk("%lld", (long long)s64_var);
21
22If <type> is dependent on a config option for its size (e.g., sector_t,
23blkcnt_t, phys_addr_t, resource_size_t) or is architecture-dependent
24for its size (e.g., tcflag_t), use a format specifier of its largest
25possible type and explicitly cast to it. Example:
26
27 printk("test: sector number/total blocks: %llu/%llu\n",
28 (unsigned long long)sector, (unsigned long long)blockcount);
29
30Reminder: sizeof() result is of type size_t.
31
32Thank you for your cooperation and attention.
33
34
35By Randy Dunlap <rdunlap@xenotime.net>