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authorIngo Molnar <mingo@elte.hu>2008-12-16 22:04:48 +0100
committerIngo Molnar <mingo@elte.hu>2008-12-16 22:04:48 +0100
commit78f902ccc597d6ce3e8d1477d70f2d79e960ba7a (patch)
treec6ceab663de16501d1dda1c1596fe2dacaaef8e3 /Documentation/printk-formats.txt
parent9ee670fd87b7d69c8633b94c42aadcbbcb96f28e (diff)
parent8b1fae4e4200388b64dd88065639413cb3f1051c (diff)
Merge commit 'v2.6.28-rc8' into x86/doc
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+If variable is of Type, use printk format specifier:
+---------------------------------------------------------
+ int %d or %x
+ unsigned int %u or %x
+ long %ld or %lx
+ unsigned long %lu or %lx
+ long long %lld or %llx
+ unsigned long long %llu or %llx
+ size_t %zu or %zx
+ ssize_t %zd or %zx
+
+Raw pointer value SHOULD be printed with %p.
+
+u64 SHOULD be printed with %llu/%llx, (unsigned long long):
+
+ printk("%llu", (unsigned long long)u64_var);
+
+s64 SHOULD be printed with %lld/%llx, (long long):
+
+ printk("%lld", (long long)s64_var);
+
+If <type> is dependent on a config option for its size (e.g., sector_t,
+blkcnt_t, phys_addr_t, resource_size_t) or is architecture-dependent
+for its size (e.g., tcflag_t), use a format specifier of its largest
+possible type and explicitly cast to it. Example:
+
+ printk("test: sector number/total blocks: %llu/%llu\n",
+ (unsigned long long)sector, (unsigned long long)blockcount);
+
+Reminder: sizeof() result is of type size_t.
+
+Thank you for your cooperation and attention.
+
+
+By Randy Dunlap <rdunlap@xenotime.net>