strerror

 

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strerror

 

Defined in header <string.h>
char* strerror( int errnum );

Returns text version of the error code errnum. errnum is usually acquired from the errno variable, however the function accepts any value of type int. The message is locale-specific.

The returned byte string must not be modified by the program, but may be overwritten by a subsequent call to the strerror function.

Parameters

errnum

-

integral value referring to a error code

Return value

Pointer to a null-terminated byte string corresponding to the error code errnum.

Example

Run this code

#include <stdio.h>
#include <errno.h>
#include <string.h>
 
int main(void)
{
    FILE *fp;
    char *path = "/path/to/non_existing_file";
 
    errno = 0;
    if ((fp = fopen(path, "r")) == NULL) {
        char *error_str = strerror(errno);
        printf("Can't open \"%s\": %s\n", path, error_str);
    }
    printf("Error string for EINVAL: %s\n", strerror(EINVAL));
 
    return 0;
}

Output:

Can't open "/path/to/non_existing_file": No such file or directory
Error string for EINVAL: Invalid argument

See also

C++ documentation for strerror