GCVT(3) Linux Programmers Manual GCVT(3)
gcvt - convert a floating-point number to a string
char *gcvt(double number, size_t ndigit, char *buf);
Feature Test Macro Requirements for glibc (see feature_test_macros(7)):
gcvt(): _SVID_SOURCE || _XOPEN_SOURCE >= 500
The gcvt() function converts number to a minimal length NULL terminated
ASCII string and stores the result in buf. It produces ndigit signifi
cant digits in either printf(3) F format or E format.
The gcvt() function returns the address of the string pointed to by
marked as LEGACY in POSIX.1-2001.
This function is obsolete. Instead, sprintf(3) is recommended.
ecvt(3), fcvt(3), sprintf(3)
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