sprintf(3) — Linux manual page

sprintf(3)               Library Functions Manual              sprintf(3)

NAME         top

       sprintf, vsprintf - string print formatted

LIBRARY         top

       Standard C library (libc, -lc)

SYNOPSIS         top

       #include <stdio.h>

       int sprintf(char *restrict str,
                   const char *restrict format, ...);
       int vsprintf(char *restrict str,
                   const char *restrict format, va_list ap);

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

       snprintf(), vsnprintf():
           _XOPEN_SOURCE >= 500 || _ISOC99_SOURCE
               || /* glibc <= 2.19: */ _BSD_SOURCE

DESCRIPTION         top

       These functions are equivalent to snprintf(3) and vsnprintf(3),
       except that no check for buffer overrun is performed (see BUGS
       below).

ATTRIBUTES         top

       For an explanation of the terms used in this section, see
       attributes(7).
       ┌───────────────────────────────┬───────────────┬────────────────┐
       │ Interface                     │ Attribute     │ Value          │
       ├───────────────────────────────┼───────────────┼────────────────┤
       │ sprintf(), vsprintf()         │ Thread safety │ MT-Safe locale │
       └───────────────────────────────┴───────────────┴────────────────┘

STANDARDS         top

       C11, POSIX.1-2008.

HISTORY         top

       C89, POSIX.1-2001.

BUGS         top

       See printf(3).

   sprintf(), vsprintf()
       Because sprintf() and vsprintf() assume an arbitrarily long
       string, callers must be careful not to overflow the actual space;
       this is often impossible to assure.  Note that the length of the
       strings produced is locale-dependent and difficult to predict.
       Use snprintf() and vsnprintf() instead (or asprintf(3) and
       vasprintf(3)).

SEE ALSO         top

       asprintf(3), snprintf(3)

COLOPHON         top

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Linux man-pages 6.18            2025-12-07                     sprintf(3)

Pages that refer to this page: gawk(1),  aprintf(3),  asprintf(3),  ecvt(3),  ecvt_r(3),  gcvt(3),  lber-encode(3),  qecvt(3),  sscanf(3),  stdio(3),  strfmon(3),  strftime(3),  wprintf(3),  slapd.conf(5),  slapd-config(5),  feature_test_macros(7),  slappasswd(8)

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