Originální popis anglicky:
unlink - delete a name and possibly the file it refers to
Návod, kniha: Linux Programmer's Manual
#include <unistd.h>
int unlink(const char *pathname);
unlink deletes a name from the filesystem. If that name was the last link
to a file and no processes have the file open the file is deleted and the
space it was using is made available for reuse.
If the name was the last link to a file but any processes still have the file
open the file will remain in existence until the last file descriptor
referring to it is closed.
If the name referred to a symbolic link the link is removed.
If the name referred to a socket, fifo or device the name for it is removed but
processes which have the object open may continue to use it.
On success, zero is returned. On error, -1 is returned, and
errno is set
appropriately.
- EACCES
- Write access to the directory containing pathname is
not allowed for the process's effective UID, or one of the directories in
pathname did not allow search permission. (See also
path_resolution(2).)
- EBUSY (not on Linux)
- The file pathname cannot be unlinked because it is
being used by the system or another process and the implementation
considers this an error.
- EFAULT
- pathname points outside your accessible address
space.
- EIO
- An I/O error occurred.
- EISDIR
- pathname refers to a directory. (This is the
non-POSIX value returned by Linux since 2.1.132.)
- ELOOP
- Too many symbolic links were encountered in translating
pathname.
- ENAMETOOLONG
- pathname was too long.
- ENOENT
- A component in pathname does not exist or is a
dangling symbolic link, or pathname is empty.
- ENOMEM
- Insufficient kernel memory was available.
- ENOTDIR
- A component used as a directory in pathname is not,
in fact, a directory.
- EPERM
- The system does not allow unlinking of directories, or
unlinking of directories requires privileges that the current process
doesn't have. (This is the POSIX prescribed error return.)
- EPERM (Linux only)
- The filesystem does not allow unlinking of files.
- EPERM or EACCES
- The directory containing pathname has the sticky bit
(S_ISVTX) set and the process's effective UID is neither the UID of
the file to be deleted nor that of the directory containing it, and the
process is not privileged (Linux: does not have the CAP_FOWNER
capability).
- EROFS
- pathname refers to a file on a read-only
filesystem.
SVr4, SVID, POSIX, X/OPEN, 4.3BSD. SVr4 documents additional error conditions
EINTR, EMULTIHOP, ETXTBSY, ENOLINK.
Infelicities in the protocol underlying NFS can cause the unexpected
disappearance of files which are still being used.
rm(1),
chmod(2),
link(2),
mknod(2),
open(2),
path_resolution(2),
rename(2),
rmdir(2),
mkfifo(3),
remove(3)
