/* vsprintf with automatic memory allocation in C locale. Copyright (C) 2002-2004, 2007-2023 Free Software Foundation, Inc. This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, either version 3, or (at your option) any later version. This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with this program; if not, see . */ #ifndef _C_VASNPRINTF_H #define _C_VASNPRINTF_H /* This file uses _GL_ATTRIBUTE_FORMAT. */ #if !_GL_CONFIG_H_INCLUDED #error "Please include config.h first." #endif /* Get va_list. */ #include /* Get size_t. */ #include /* Get _GL_ATTRIBUTE_SPEC_PRINTF_STANDARD. */ #include #ifdef __cplusplus extern "C" { #endif /* Write formatted output to a string dynamically allocated with malloc(). You can pass a preallocated buffer for the result in RESULTBUF and its size in *LENGTHP; otherwise you pass RESULTBUF = NULL. If successful, return the address of the string (this may be = RESULTBUF if no dynamic memory allocation was necessary) and set *LENGTHP to the number of resulting bytes, excluding the trailing NUL. Upon error, set errno and return NULL. When dynamic memory allocation occurs, the preallocated buffer is left alone (with possibly modified contents). This makes it possible to use a statically allocated or stack-allocated buffer, like this: char buf[100]; size_t len = sizeof (buf); char *output = vasnprintf (buf, &len, format, args); if (output == NULL) ... error handling ...; else { ... use the output string ...; if (output != buf) free (output); } Formatting takes place in the C locale, that is, the decimal point used in floating-point formatting directives is always '.'. */ extern char *c_vasnprintf (char *restrict resultbuf, size_t *lengthp, const char *format, va_list args) _GL_ATTRIBUTE_FORMAT ((_GL_ATTRIBUTE_SPEC_PRINTF_STANDARD, 3, 0)); #ifdef __cplusplus } #endif #endif /* _C_VASNPRINTF_H */