1 /*-----------------------------------------------------------------------*/ 2 /* Get a string from the file                                            */ 3 /*-----------------------------------------------------------------------*/ 4 TCHAR* f_gets ( 5     TCHAR* buff,    /* Pointer to the string buffer to read */ 6     int len,        /* Size of string buffer (characters) */ 7     FIL* fil        /* Pointer to the file object */ 8 ) 9 {10     int n = 0;11     TCHAR c, *p = buff;12     BYTE s[2];13     UINT rc;14 15 16     while (n < len - 1) {            /* Read bytes until buffer gets filled */17         f_read(fil, s, 1, &rc);18         if (rc != 1) break;            /* Break on EOF or error */19         c = s[0];20 #if _LFN_UNICODE                    /* Read a character in UTF-8 encoding */21         if (c >= 0x80) {22             if (c < 0xC0) continue;    /* Skip stray trailer */23             if (c < 0xE0) {            /* Two-byte sequense */24                 f_read(fil, s, 1, &rc);25                 if (rc != 1) break;26                 c = ((c & 0x1F) << 6) | (s[0] & 0x3F);27                 if (c < 0x80) c = ‘?‘;28             } else {29                 if (c < 0xF0) {        /* Three-byte sequense */30                     f_read(fil, s, 2, &rc);31                     if (rc != 2) break;32                     c = (c << 12) | ((s[0] & 0x3F) << 6) | (s[1] & 0x3F);33                     if (c < 0x800) c = ‘?‘;34                 } else {            /* Reject four-byte sequense */35                     c = ‘?‘;36                 }37             }38         }39 #endif40 #if _USE_STRFUNC >= 241         if (c == ‘\r‘) continue;    /* Strip ‘\r‘ */42 #endif43         *p++ = c;44         n++;45         if (c == ‘\n‘) break;        /* Break on EOL */46     }47     *p = 0;48     return n ? buff : 0;            /* When no data read (eof or error), return with error. */49 }

 1 /*-----------------------------------------------------------------------*/ 2 /* Put a character to the file                                           */ 3 /*-----------------------------------------------------------------------*/ 4 int f_putc ( 5     TCHAR c,    /* A character to be output */ 6     FIL* fil    /* Pointer to the file object */ 7 ) 8 { 9     UINT bw, btw;10     BYTE s[3];11 12 13 #if _USE_STRFUNC >= 214     if (c == ‘\n‘) f_putc (‘\r‘, fil);    /* LF -> CRLF conversion */15 #endif16 17 #if _LFN_UNICODE    /* Write the character in UTF-8 encoding */18     if (c < 0x80) {            /* 7-bit */19         s[0] = (BYTE)c;20         btw = 1;21     } else {22         if (c < 0x800) {    /* 11-bit */23             s[0] = (BYTE)(0xC0 | (c >> 6));24             s[1] = (BYTE)(0x80 | (c & 0x3F));25             btw = 2;26         } else {            /* 16-bit */27             s[0] = (BYTE)(0xE0 | (c >> 12));28             s[1] = (BYTE)(0x80 | ((c >> 6) & 0x3F));29             s[2] = (BYTE)(0x80 | (c & 0x3F));30             btw = 3;31         }32     }33 #else                /* Write the character without conversion */34     s[0] = (BYTE)c;35     btw = 1;36 #endif37     f_write(fil, s, btw, &bw);        /* Write the char to the file */38     return (bw == btw) ? 1 : EOF;    /* Return the result */39 }

 1 /*-----------------------------------------------------------------------*/ 2 /* Put a string to the file                                              */ 3 /*-----------------------------------------------------------------------*/ 4 int f_puts ( 5     const TCHAR* str,    /* Pointer to the string to be output */ 6     FIL* fil            /* Pointer to the file object */ 7 ) 8 { 9     int n;10 11 12     for (n = 0; *str; str++, n++) {13         if (f_putc(*str, fil) == EOF) return EOF;14     }15     return n;16 }

 1 /*-----------------------------------------------------------------------*/ 2 /* Put a formatted string to the file                                    */ 3 /*-----------------------------------------------------------------------*/ 4 int f_printf ( 5     FIL* fil,            /* Pointer to the file object */ 6     const TCHAR* str,    /* Pointer to the format string */ 7     ...                    /* Optional arguments... */ 8 ) 9 {10     va_list arp;11     BYTE f, r;12     UINT i, j, w;13     ULONG v;14     TCHAR c, d, s[16], *p;15     int res, chc, cc;16 17 18     va_start(arp, str);19 20     for (cc = res = 0; cc != EOF; res += cc) {21         c = *str++;22         if (c == 0) break;            /* End of string */23         if (c != ‘%‘) {                /* Non escape character */24             cc = f_putc(c, fil);25             if (cc != EOF) cc = 1;26             continue;27         }28         w = f = 0;29         c = *str++;30         if (c == ‘0‘) {                /* Flag: ‘0‘ padding */31             f = 1; c = *str++;32         } else {33             if (c == ‘-‘) {            /* Flag: left justified */34                 f = 2; c = *str++;35             }36         }37         while (IsDigit(c)) {        /* Precision */38             w = w * 10 + c - ‘0‘;39             c = *str++;40         }41         if (c == ‘l‘ || c == ‘L‘) {    /* Prefix: Size is long int */42             f |= 4; c = *str++;43         }44         if (!c) break;45         d = c;46         if (IsLower(d)) d -= 0x20;47         switch (d) {                /* Type is... */48         case ‘S‘ :                    /* String */49             p = va_arg(arp, TCHAR*);50             for (j = 0; p[j]; j++) ;51             chc = 0;52             if (!(f & 2)) {53                 while (j++ < w) chc += (cc = f_putc(‘ ‘, fil));54             }55             chc += (cc = f_puts(p, fil));56             while (j++ < w) chc += (cc = f_putc(‘ ‘, fil));57             if (cc != EOF) cc = chc;58             continue;59         case ‘C‘ :                    /* Character */60             cc = f_putc((TCHAR)va_arg(arp, int), fil); continue;61         case ‘B‘ :                    /* Binary */62             r = 2; break;63         case ‘O‘ :                    /* Octal */64             r = 8; break;65         case ‘D‘ :                    /* Signed decimal */66         case ‘U‘ :                    /* Unsigned decimal */67             r = 10; break;68         case ‘X‘ :                    /* Hexdecimal */69             r = 16; break;70         default:                    /* Unknown type (passthrough) */71             cc = f_putc(c, fil); continue;72         }73 74         /* Get an argument and put it in numeral */75         v = (f & 4) ? (ULONG)va_arg(arp, long) : ((d == ‘D‘) ? (ULONG)(long)va_arg(arp, int) : (ULONG)va_arg(arp, unsigned int));76         if (d == ‘D‘ && (v & 0x80000000)) {77             v = 0 - v;78             f |= 8;79         }80         i = 0;81         do {82             d = (TCHAR)(v % r); v /= r;83             if (d > 9) d += (c == ‘x‘) ? 0x27 : 0x07;84             s[i++] = d + ‘0‘;85         } while (v && i < sizeof(s) / sizeof(s[0]));86         if (f & 8) s[i++] = ‘-‘;87         j = i; d = (f & 1) ? ‘0‘ : ‘ ‘;88         res = 0;89         while (!(f & 2) && j++ < w) res += (cc = f_putc(d, fil));90         do res += (cc = f_putc(s[--i], fil)); while(i);91         while (j++ < w) res += (cc = f_putc(‘ ‘, fil));92         if (cc != EOF) cc = res;93     }94 95     va_end(arp);96     return (cc == EOF) ? cc : res;97 }

 1 f_gets(buf, NUM, &fil);            // 从文件中读取一个字符串的前 NUM个字符 2 f_putc(ch, &fil);                // 向文件中写入一个字符 3 f_puts((char *)buffer, &fil);    // 向文件内写入一个字符串 4  5 f_printf(&fil, "%6d", -200);         /* "  -200" */ 6 f_printf(&fil, "%02u", 5);           /* "05" */ 7 f_printf(&fil, "%ld", 12345678L);    /* "12345678" */ 8 f_printf(&fil, "%08lX", 1194684UL);  /* "00123ABC" */ 9 f_printf(&fil, "%s", "String");      /* "String" */10 f_printf(&fil, "%c", ‘a‘);           /* "a" */