c - convert IP for reverse ip lookup -

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i have ip address e.g. char *ip = "192.168.1.13" , need convert "13.1.168.192" there proper possibility in c or have myself making tokens , putting them again?

you use inet_pton convert binary form, making easy reverse, , convert text inet_ntop.

remember ipv4 address 32-bit unsigned integer. swapping bytes around of easy.

something this:

const char ip[] = "192.168.0.1"; char reversed_ip[inet_addrstrlen];  in_addr_t addr;  /* textual address binary format */ inet_pton(af_inet, ip, &addr);  /* reverse bytes in binary address */ addr =     ((addr & 0xff000000) >> 24) |     ((addr & 0x00ff0000) >>  8) |     ((addr & 0x0000ff00) <<  8) |     ((addr & 0x000000ff) << 24);  /* , lastly textual representation again */ inet_ntop(af_inet, &addr, reversed_ip, sizeof(reversed_ip));

after code, variable reversed_ip contains revered address string.


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