Go to most recent revision | Details | Last modification | View Log | RSS feed
| Rev | Author | Line No. | Line |
|---|---|---|---|
| 7184 | siemargl | 1 | /* ungetc example */ |
| 2 | #include |
||
| 3 | |||
| 4 | void trace_file(FILE* f, char* cmt); |
||
| 5 | |||
| 6 | int main () |
||
| 7 | { |
||
| 8 | FILE * pFile; |
||
| 9 | int c; |
||
| 10 | char buffer [256]; |
||
| 11 | |||
| 12 | pFile = fopen ("myfile.txt","rt"); |
||
| 13 | if (pFile==NULL) perror ("Error opening file"); |
||
| 14 | else while (!feof (pFile)) { |
||
| 15 | trace_file(pFile, "1"); |
||
| 16 | |||
| 17 | c=getc (pFile); |
||
| 18 | |||
| 19 | trace_file(pFile, "before ungetc"); |
||
| 20 | |||
| 21 | if (c == EOF) break; |
||
| 22 | if (c == '#') ungetc ('@',pFile); |
||
| 23 | else ungetc (c,pFile); |
||
| 24 | |||
| 25 | trace_file(pFile, "after"); |
||
| 26 | |||
| 27 | if (fgets (buffer,255,pFile) != NULL) |
||
| 28 | puts (buffer); |
||
| 29 | else break; |
||
| 30 | } |
||
| 31 | return 0; |
||
| 32 | } |
||
| 33 | |||
| 34 | void trace_file(FILE* f, char* cmt) |
||
| 35 | { |
||
| 36 | printf("%s[%s]\n", cmt, f->buffer); |
||
| 37 | printf("mode=%0X, filesize=%d, filepos=%d\n", f->mode, f->filesize, f->filepos); |
||
| 38 | printf("ungetc=%d, buffer_start=%d, buffer_end=%d\n", f->ungetc_buf, f->buffer_start, f->buffer_end); |
||
| 39 | } |