pmNumberStr man page

pmNumberStr, pmNumberStr_r — fixed width output format for numbers

C Synopsis

#include <pcp/pmapi.h>

const char *pmNumberStr(double value);
char *pmNumberStr_r(double value, char *buf, int buflen);

cc ... -lpcp


pmNumberStr returns the address of a 8-byte buffer that holds a null-byte terminated representation of value suitable for output with fixed width fields. The pmNumberStr_r function does the same, but stores the result in a user-supplied buffer buf of length buflen, which should have room for at least 8 bytes.

The value is scaled using multipliers in powers of “one thousand” (the decimal “kilo”) and has a bias that provides greater precision for positive numbers as opposed to negative numbers.

The format depends on the sign and magnitude of value as follows (d represents a decimal digit):

value rangeformat
> 999995000000000 inf?
999995000000000 - 999995000000ddd.ddT
999995000000 - 999995000ddd.ddG
999995000 - 999995ddd.ddM
999995 - 999.995ddd.ddK
999.995 - 0.005ddd.dd
0.005 - -0.005 0.00
-0.005 - -99.95-dd.dd
-99.995 - -99995-dd.ddK
-99995 - -99995000-dd.ddM
-99995000 - -99995000000-dd.ddG
-99995000000 - -99995000000000-dd.ddT
< -99995000000000-inf?

At the boundary points of the ranges, the chosen format will retain the maximum number of significant digits.


pmNumberStr returns a pointer to a static buffer and hence is not thread-safe. Multi-threaded applications should use pmNumberStr_r instead.

See Also


Referenced By

pmnumberstr(3) is an alias of pmNumberStr(3).

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