Syntax

• #include <stdio.h> /* Include this to use any of the following sections */
• FILE *fopen(const char *path, const char mode); / Open a stream on the file at path with the specified mode */
• FILE *freopen(const char *path, const char *mode, FILE stream); / Re-open an existing stream on the file at path with the specified mode */
• int fclose(FILE stream); / Close an opened stream */
• size_t fread(void *ptr, size_t size, size_t nmemb, FILE stream); / Read at most nmemb elements of size bytes each from the stream and write them in ptr. Returns the number of read elements. */
• size_t fwrite(const void *ptr, size_t size, size_t nmemb, FILE stream); / Write nmemb elements of size bytes each from ptr to the stream. Returns the number of written elements. */
• int fseek(FILE stream, long offset, int whence); / Set the cursor of the stream to offset, relative to the offset told by whence, and returns 0 if it succeeded. */
• long ftell(FILE stream); / Return the offset of the current cursor position from the beginning of the stream. */
• void rewind(FILE stream); / Set the cursor position to the beginning of the file. */
• int fprintf(FILE *fout, const char fmt, …); / Writes printf format string on fout */
• FILE stdin; / Standard input stream */
• FILE stdout; / Standard output stream */
• FILE stderr; / Standard error stream */

Parameters

Parameter | Details |

——— | —–– |

const char *mode | A string describing the opening mode of the file-backed stream. See remarks for possible values. | int whence | Can be SEEK_SET to set from the beginning of the file, SEEK_END to set from its end, or SEEK_CUR to set relative to the current cursor value. Note: SEEK_END is non-portable.|

Remarks

Mode strings: