c - va_start va_end with fatfs f_printf -

i'm trying implement function, write sdcard. should called printf additional optional arguments:

    void writedatatofiles(int anything,         const tchar* fmt, ...){              ....             va_list args;             va_start(args, fmt);             f_printf(file, fmt, args); //this doesnt work             vprintf(fmt, args); //this works             va_end(args);             f_sync(file); ... } 

i try call this

int m=5 writedatatofiles(0,"my int value %i\n", m); 

vprintf work, f_printf saving string "i" instead of replacing actual value

this f_printf implementation

    /*-----------------------------------------------------------------------*/ /* put formatted string file                                    */ /*-----------------------------------------------------------------------*/ int f_printf(fil* fil, /* pointer file object */ const tchar* str, /* pointer format string */ ... /* optional arguments... */ ) {     va_list arp;     byte f, r;     uint i, j, w;     ulong v;     tchar c, d, s[16], *p;     int res, cc;      va_start(arp, str);      (cc = res = 0; cc != eof; res += cc) {         c = *str++;         if (c == 0)             break; /* end of string */         if (c != '%') { /* non escape character */             cc = f_putc(c, fil);             if (cc != eof)                 cc = 1;             continue;         }         w = f = 0;         c = *str++;         if (c == '0') { /* flag: '0' padding */             f = 1;             c = *str++;         } else {             if (c == '-') { /* flag: left justified */                 f = 2;                 c = *str++;             }         }         while (isdigit(c)) { /* precision */             w = w * 10 + c - '0';             c = *str++;         }         if (c == 'l' || c == 'l') { /* prefix: size long int */             f |= 4;             c = *str++;         }         if (!c)             break;         d = c;         if (islower(d))             d -= 0x20;         switch (d) { /* type is... */             case 's': /* string */                 p = va_arg(arp, tchar*);                 (j = 0; p[j]; j++)                     ;                 res = 0;                 while (!(f & 2) && j++ < w)                     res += (cc = f_putc(' ', fil));                 res += (cc = f_puts(p, fil));                 while (j++ < w)                     res += (cc = f_putc(' ', fil));                 if (cc != eof)                     cc = res;                 continue;             case 'c': /* character */                 cc = f_putc((tchar) va_arg(arp, int), fil);                 continue;             case 'b': /* binary */                 r = 2;                 break;             case 'o': /* octal */                 r = 8;                 break;             case 'd': /* signed decimal */             case 'u': /* unsigned decimal */                 r = 10;                 break;             case 'x': /* hexdecimal */                 r = 16;                 break;             default: /* unknown type (passthrough) */                 cc = f_putc(c, fil);                 continue;         }          /* argument , put in numeral */         v = (f & 4) ? va_arg(arp, long) : ((d == 'd') ? (long) va_arg(arp, int)                 : va_arg(arp, unsigned int));         if (d == 'd' && (v & 0x80000000)) {             v = 0 - v;             f |= 8;         }         = 0;         {             d = (tchar) (v % r);             v /= r;             if (d > 9)                 d += (c == 'x') ? 0x27 : 0x07;             s[i++] = d + '0';         } while (v && < sizeof(s) / sizeof(s[0]));         if (f & 8)             s[i++] = '-';         j = i;         d = (f & 1) ? '0' : ' ';         res = 0;         while (!(f & 2) && j++ < w)             res += (cc = f_putc(d, fil));                     res += (cc = f_putc(s[--i], fil));         while (i);         while (j++ < w)             res += (cc = f_putc(' ', fil));         if (cc != eof)             cc = res;     }      va_end(arp);     return (cc == eof) ? cc : res; } 

edit: tried use va_list parameter f_print method, still doesnt work:

int f_printf(fil* fil, /* pointer file object */ const tchar* str, /* pointer format string */ va_list arp /* optional arguments... */ ) {     byte f, r;     uint i, j, w;     ulong v;     tchar c, d, s[16], *p;     int res, cc;     (cc = res = 0; cc != eof; res += cc) {         c = *str++;         if (c == 0)             break; /* end of string */         if (c != '%') { /* non escape character */             cc = f_putc(c, fil);             if (cc != eof)                 cc = 1;             continue;         }         w = f = 0;         c = *str++;         if (c == '0') { /* flag: '0' padding */             f = 1;             c = *str++;         } else {             if (c == '-') { /* flag: left justified */                 f = 2;                 c = *str++;             }         }         while (isdigit(c)) { /* precision */             w = w * 10 + c - '0';             c = *str++;         }         if (c == 'l' || c == 'l') { /* prefix: size long int */             f |= 4;             c = *str++;         }         if (!c)             break;         d = c;         if (islower(d))             d -= 0x20;         switch (d) { /* type is... */             case 's': /* string */                 p = va_arg(arp, tchar*);                 (j = 0; p[j]; j++)                     ;                 res = 0;                 while (!(f & 2) && j++ < w)                     res += (cc = f_putc(' ', fil));                 res += (cc = f_puts(p, fil));                 while (j++ < w)                     res += (cc = f_putc(' ', fil));                 if (cc != eof)                     cc = res;                 continue;             case 'c': /* character */                 cc = f_putc((tchar) va_arg(arp, int), fil);                 continue;             case 'b': /* binary */                 r = 2;                 break;             case 'o': /* octal */                 r = 8;                 break;             case 'd': /* signed decimal */             case 'u': /* unsigned decimal */                 r = 10;                 break;             case 'x': /* hexdecimal */                 r = 16;                 break;             default: /* unknown type (passthrough) */                 cc = f_putc(c, fil);                 continue;         }          /* argument , put in numeral */         v = (f & 4) ? va_arg(arp, long) : ((d == 'd') ? (long) va_arg(arp, int)                 : va_arg(arp, unsigned int));         if (d == 'd' && (v & 0x80000000)) {             v = 0 - v;             f |= 8;         }         = 0;         {             d = (tchar) (v % r);             v /= r;             if (d > 9)                 d += (c == 'x') ? 0x27 : 0x07;             s[i++] = d + '0';         } while (v && < sizeof(s) / sizeof(s[0]));         if (f & 8)             s[i++] = '-';         j = i;         d = (f & 1) ? '0' : ' ';         res = 0;         while (!(f & 2) && j++ < w)             res += (cc = f_putc(d, fil));                     res += (cc = f_putc(s[--i], fil));         while (i);         while (j++ < w)             res += (cc = f_putc(' ', fil));         if (cc != eof)             cc = res;     }      return (cc == eof) ? cc : res; }