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将存储在uint32_t中的内存转换为C中的浮点数

[英]cast the memory stored in a uint32_t as a float in C

Having a Hex represented as a string in c 将十六进制表示为c中的字符串
eg char* text = "0xffff" 例如, char* text = "0xffff"
I manage to hold the data in a uint32_t with the following function: 我设法通过以下功能将数据保存在uint32_t

for (unsigned int i = 0; i < line_length && count < WORD_SIZE; i++) {
        char c[2]; //represent the digit as string
        c[0] = line[i];
        c[1] = '\0';
        if (isxdigit(c[0])) { //we've found a relevant char.
            res_out <<= 4; // shift left by 4 for the next 4 bits.
            res_out += (int32_t)strtol(c, NULL, 16); //set the last 4 bits bit to relevant value
                                                     //res_out <<= 4; // shift left by 4 for the next 4 bits.
            count += 4;
        }
    }

Now, having the 32 bits, the uint32_t sometimes represented a single-precision floating point number, and I would like to parse it as such 现在,具有32位,uint32_t 有时表示一个单精度浮点数,我想这样解析它
Using float f = (float)num of course casts the int representation to float (not the needed operation) and I have no other idea's how to tell memory it's actually a floating point number 当然使用float f = (float)num会将int表示形式强制转换为float(不是必需的操作),我不知道如何告诉内存它实际上是一个浮点数

Just for future references, As @melpomene suggested 仅供以后参考,如@melpomene所建议

uint32_t x = /* some single precision float value dumped into a uint32_t*/;
uint32_t float_placeholder = 0;
memcpy(&float_placeholder, &x, sizeof(uint32_t));

float_placeholder holds the true floating point number float_placeholder持有真实的浮点数

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