sprintf(3)                 Library Functions Manual                 sprintf(3)

NAME
       sprintf, vsprintf - string print formatted

LIBRARY
       Standard C library (libc, -lc)

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

ATTRIBUTES
       For an explanation of the terms used in this section, see
       attributes(7).

       +-------------------------------------+---------------+----------------+
       |Interface                            | Attribute     | Value          |
       +-------------------------------------+---------------+----------------+
       |sprintf (), vsprintf ()              | Thread safety | MT-Safe locale |
       +-------------------------------------+---------------+----------------+
STANDARDS
       C11, POSIX.1-2008.

HISTORY
       C89, POSIX.1-2001.

BUGS
       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
       asprintf(3), snprintf(3)

Linux man-pages 6.19              2025-12-07                        sprintf(3)