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/* * vasprintf.c */ #include <stdio.h> #include <stdlib.h> #include <stdarg.h> int vasprintf(char **bufp, const char *format, va_list ap) { va_list ap1; int bytes; char *p; va_copy(ap1, ap); bytes = vsnprintf(NULL, 0, format, ap1) + 1; va_end(ap1); *bufp = p = malloc(bytes); if (!p) return -1; return vsnprintf(p, bytes, format, ap); }