The ferror () function in C

The int ferror function (FILE * stream) in Library C checks the error indicator for the given Stream.

Declare the function ferror () in C

Below is the declaration for the ferror () function in C:

 int ferror ( FILE * stream ) 

Parameters

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

Returns the value

If the Error Indicator that binds to the Stream is set, the function returns a value other than zero. Otherwise, the function returns 0.

For example

The following C program illustrates the usage of the ferror () 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 opened in write only mode.

The ferror () function in C Picture 1

According to Tutorialspoint

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