...
| Code Block |
|---|
|
struct stat st;
dev_t dev; /* device */
ino_t ino; /* file serial number */
int fd = open(filename, O_RDWR);
if ( (fd != -1) &&
(fstat(fd, &st) != -1) &&
(st.st_ino == ino) &&
(st.st_dev == dev)
) {
...
}
close(fd);
|
The structure members st_mode, st_ino, st_dev, st_uid, st_gid, st_atime, st_ctime, and st_mtime should all have meaningful values for all file types on POSIX compliant systems. The st_ino field contains the file serial number. The st_dev field identifies the device containing the file. The st_ino and st_dev, taken together, uniquely identifies the file. The st_dev value is not necessarily consistent across reboots or system crashes, however.
...
| Code Block |
|---|
|
struct stat st;
dev_t dev = 773; /* device */
ino_t ino = 11321585; /* file serial number */
FILE *fd = fopen(filename, "r");
if ( (fd) &&
(fstat(fileno(fd), &st) != -1) &&
(st.st_ino == ino) &&
(st.st_dev == dev)
) {
...
}
fclose(fd);
|
Risk Assessment
...
| Wiki Markup |
|---|
\[[Seacord 05|AA. C References#Seacord 05]\] Chapter 7, "File I/O"
\[[ISO/IEC 9899-1999|AA. C References#ISO/IEC 9899-1999]\] SectionsSection 7.19.3, Files;"Files," and Section 7.19.4, "Operations on Files"
\[[Open Group 04|AA. C References#Open Group 04]\] "The open function," "The fstat function"
\[[Drepper 06|AA. C References#Drepper 06]\] Section 2.2.1 "Identification When Opening" |
