Package: manpages-dev
Version: 3.74-1
The man page for quotactl reports the following for the struct dqblk under
Q_GETQUOTA:
uint64_t dqb_curspace; /* current quota block count */
Which seems to be referencing the sys/quota.h file, which comes from the
libc6-dev package (version 2.19-18+deb8u3):
dpkg -S /usr/include/x86_64-linux-gnu/sys/quota.h
libc6-dev:amd64: /usr/include/x86_64-linux-gnu/sys/quota.h
Which also has the same comment. The comment is incorrect, dqb_curspace is
in bytes, not blocks.
It is trivial to write a small c++ program to verify this:
#include <sys/quota.h>
#include <iostream>
#include <cstring>
#include <string>
#include <cerrno>
void printquota(std::string device, int gid) {
struct dqblk dq;
if(quotactl(QCMD(Q_GETQUOTA, GRPQUOTA), device.c_str(), gid, (char*)&dq))
{
std::cout << "Got an error: " << std::strerror(errno) << std::endl;
}
std::cout << "Device: " << device << " Group: " << gid << " Space: " <<
dq.dqb_curspace << std::endl;
}
int main() {
printquota("/dev/<your_device>",<your gid>);
}
Looking at the source code for the kernel, we can also see in
include/linux/quota.h that it doesn't say it is in blocks:
qsize_t dqb_curspace; /* current used space */
Weaving through the kernel code that actually increments the value, it can
be seen that it is represented in bytes (include/linux/quotaops.h):
static inline int dquot_alloc_block(struct inode *inode, qsize_t nr)
{
return dquot_alloc_space(inode, nr << inode->i_blkbits);
}
