Section (3) asprintf
asprintf, vasprintf — print to allocated string
#define _GNU_SOURCE /* See feature_test_macros(7) */ #include <stdio.h>
|const char *fmt,|
|const char *fmt,|
vasprintf() are analogs of
sprintf(3) and vsprintf(3), except that
they allocate a string large enough to hold the output
including the terminating null byte (_zsingle_quotesz_ _zsingle_quotesz_), and return a
pointer to it via the first argument. This pointer should be
passed to free(3) to release the
allocated storage when it is no longer needed.
When successful, these functions return the number of
bytes printed, just like sprintf(3). If memory
allocation wasn_zsingle_quotesz_t possible, or some other error occurs, these
functions will return −1, and the contents of
For an explanation of the terms used in this section, see attributes(7).
||Thread safety||MT-Safe locale|
These functions are GNU extensions, not in C or POSIX.
They are also available under *BSD. The FreeBSD
strp to NULL on error.
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Copyright (C) 2001 Andries Brouwer <aebcwi.nl>
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