gcvt(3) Library Functions Manual gcvt(3)
NAME
gcvt - convert a floating-point number to a string
LIBRARY
Standard C library (libc, -lc)
SYNOPSIS
#include <stdlib.h>
char *gcvt(double number, int ndigit, char *buf);
Feature Test Macro Requirements for glibc (see feature_test_macros(7)):
gcvt():
Since glibc 2.17
(_XOPEN_SOURCE >= 500 && ! (_POSIX_C_SOURCE >= 200809L))
|| /* glibc >= 2.20 */ _DEFAULT_SOURCE
|| /* glibc <= 2.19 */ _SVID_SOURCE
glibc 2.12 to glibc 2.16:
(_XOPEN_SOURCE >= 500 && ! (_POSIX_C_SOURCE >= 200112L))
|| _SVID_SOURCE
Before glibc 2.12:
_SVID_SOURCE || _XOPEN_SOURCE >= 500
DESCRIPTION
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.
RETURN VALUE
The gcvt() function returns buf.
ATTRIBUTES
For an explanation of the terms used in this section, see attributes(7).
┌────────────────────────────────────────────┬───────────────┬─────────┐
│ Interface │ Attribute │ Value │
├────────────────────────────────────────────┼───────────────┼─────────┤
│ gcvt() │ Thread safety │ MT-Safe │
└────────────────────────────────────────────┴───────────────┴─────────┘
STANDARDS
None.
HISTORY
Marked as LEGACY in POSIX.1-2001. POSIX.1-2008 removed it, recommending
the use of sprintf(3) instead (though snprintf(3) may be preferable).
SEE ALSO
ecvt(3), fcvt(3), sprintf(3)
Linux man-pages 6.9.1 2024-05-02 gcvt(3)
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