diff options
Diffstat (limited to 'lib/vasnprintf.h')
| -rw-r--r-- | lib/vasnprintf.h | 21 |
1 files changed, 19 insertions, 2 deletions
diff --git a/lib/vasnprintf.h b/lib/vasnprintf.h index 4edb95d65..271210699 100644 --- a/lib/vasnprintf.h +++ b/lib/vasnprintf.h @@ -1,5 +1,5 @@ /* vsprintf with automatic memory allocation. - Copyright (C) 2002-2003 Free Software Foundation, Inc. + Copyright (C) 2002-2004 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 @@ -47,7 +47,24 @@ extern "C" { 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. */ + 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); + } + */ extern char * asnprintf (char *resultbuf, size_t *lengthp, const char *format, ...) __attribute__ ((__format__ (__printf__, 3, 4))); extern char * vasnprintf (char *resultbuf, size_t *lengthp, const char *format, va_list args) |