Use fread() to read binary file contents

Question

I want to use fread to read a segment of a binary file. The binary content is 0xf3 0xf 0x1e 0xfa...

But I read and output from fread() 0xfffffff3 0xf... I want to know why 0xf3 becomes 0xfffffff3 0xf 0x1e 0xfffffffa...

My implementation code is as follows:

    char movslq_inst[length];

    /* Open the target_binary */
    
    FILE * target_binary = fopen(target_path,"rb+");

    /* Jump to target address */
    if (fseek(target_binary, offset, SEEK_SET) != 0)
    {  
        printf("Unable to seek file '%s' at offset '%i", target_path, offset);
        exit(0);
    }

    /* Read the target bytes */
    if (fread(movslq_inst, length, 1, target_binary) != 1)
    { 
        printf("Unable to read file '%s'", target_path);
        exit(0);
    }

    /* test examine */
    printf("read content: \n");
    for(int i = 0; i < length; i++)
    {
        printf("0x%x ",movslq_inst[i]);
    }
    printf("\n");

Answer 1

I worked it out. It should be unsigned char movslq_inst[length]; instead of

char movslq_inst[length];.