The keyword used to declare a file pointer in C is FILE. Specifically, you declare a file pointer as:

c

FILE *filePointer;

Here, FILE is a typedef for a structure defined in the standard header <stdio.h>, which contains information about the file being handled. The pointer filePointer points to this structure and is used in file handling operations such as opening, reading, writing, and closing files

. For example:

c

FILE *fp;
fp = fopen("example.txt", "r"); // fopen returns a FILE* pointer

This declaration and usage are standard in C for working with files. The FILE type and pointers to it are essential for all file I/O functions in C