The function clearerr () in C

Void function clearerr (FILE * stream) in Library C deletes end-of-file and error indicator for the given Stream.

Declare the function clearerr () in C

Here is the declaration for the clearerr () function in C:

 void clearerr ( FILE * stream ) 

Parameters

stream - This is the pointer to a FILE object that identifies the Stream.

Returns the value

This function should fail and not set the external variable errno but in case it detects that its parameters are not a valid stream, it must return -1 and set errno to EBADF.

For example

The following C program illustrates the usage of the clearerr () function in C:

 #include int main () { FILE * fp ; char c ; fp = fopen ( "baitapc.txt" , "w" ); c = fgetc ( fp ); if ( ferror ( fp ) ) { printf ( "Da xay ra loi trong khi doc baitapc.txtn" ); } clearerr ( fp ); if ( ferror ( fp ) ) { printf ( "Da xay ra loi trong khi doc baitapc.txtn" ); } fclose ( fp ); return ( 0 ); } 

Suppose we have a text file named baitapc.txt , which is an empty file. Compiling and running this program will produce the following results. Because we try to read a file that has been opened in write-only mode (write only).

The function clearerr () in C Picture 1

According to Tutorialspoint

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