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qecvt(3) — Linux manual page

NAME | LIBRARY | SYNOPSIS | DESCRIPTION | ATTRIBUTES | STANDARDS | HISTORY | SEE ALSO | COLOPHON 

qecvt(3)                 Library Functions Manual                qecvt(3)

NAME         top

       qecvt, qfcvt, qgcvt - convert a floating-point number to a string

LIBRARY         top

       Standard C library (libc, -lc)

SYNOPSIS         top

       #include <stdlib.h>

       [[deprecated]] char *qecvt(long double number, int ndigits,
                                  int *restrict decpt, int *restrict sign);
       [[deprecated]] char *qfcvt(long double number, int ndigits,
                                  int *restrict decpt, int *restrict sign);
       [[deprecated]] char *qgcvt(long double number, int ndigit, char *buf);

   Feature Test Macro Requirements for glibc (see
   feature_test_macros(7)):

       qecvt(), qfcvt(), qgcvt():
           Since glibc 2.19:
               _DEFAULT_SOURCE
           In glibc up to and including 2.19:
               _SVID_SOURCE

DESCRIPTION         top

       The functions qecvt(), qfcvt(), and qgcvt() are identical to
       ecvt(3), fcvt(3), and gcvt(3) respectively, except that they use a
       long double argument number.  See ecvt(3) and gcvt(3).

ATTRIBUTES         top

       For an explanation of the terms used in this section, see
       attributes(7).
       โ”Œโ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”ฌโ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”ฌโ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”
       โ”‚ Interface               โ”‚ Attribute     โ”‚ Value                โ”‚
       โ”œโ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”ผโ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”ผโ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”ค
       โ”‚ qecvt()                 โ”‚ Thread safety โ”‚ MT-Unsafe race:qecvt โ”‚
       โ”œโ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”ผโ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”ผโ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”ค
       โ”‚ qfcvt()                 โ”‚ Thread safety โ”‚ MT-Unsafe race:qfcvt โ”‚
       โ”œโ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”ผโ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”ผโ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”ค
       โ”‚ qgcvt()                 โ”‚ Thread safety โ”‚ MT-Safe              โ”‚
       โ””โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”ดโ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”ดโ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”˜

STANDARDS         top

       None.

HISTORY         top

       SVr4, SunOS, GNU.

       These functions are obsolete.  Instead, snprintf(3) is
       recommended.

SEE ALSO         top

       ecvt(3), ecvt_r(3), gcvt(3), sprintf(3)

COLOPHON         top

       This page is part of the man-pages (Linux kernel and C library
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Linux man-pages 6.18            2026-02-08                       qecvt(3)

Pages that refer to this page: ecvt(3),  ecvt_r(3)

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