strmode - convert inode status information into a symbolic
string
#include <string.h>
void
strmode(mode_t mode, char *bp);
The strmode() function converts a file mode (the type and
permission information
associated with an inode, see stat(2)) into a symbolic string
which is stored in the location referenced by bp. This
stored string is
eleven characters in length plus a trailing null byte.
The first character is the inode type, and will be one of
the following:
- regular file
b block special
c character special
d directory
l symbolic link
p FIFO
s socket
w whiteout
? unknown inode type
The next nine characters encode three sets of permissions,
in three characters
each. The first three characters are the permissions
for the owner
of the file, the second three for the group the file belongs to, and
the third for the ``other'', or default, set of users.
Permission checking is done as specifically as possible. If
read permission
is denied to the owner of a file in the first set of
permissions,
the owner of the file will not be able to read the file.
This is true
even if the owner is in the file's group and the group permissions allow
reading or the ``other'' permissions allow reading.
If the first character of the three character set is an `r',
the file is
readable for that set of users; if a dash (`-'), it is not
readable.
If the second character of the three character set is a `w',
the file is
writable for that set of users; if a dash (`-'), it is not
writable.
The third character is the first of the following characters
that apply:
S If the character is part of the owner permissions and
the file is
not executable or the directory is not searchable by
the owner, and
the set-user-ID bit is set.
S If the character is part of the group permissions and
the file is
not executable or the directory is not searchable by
the group, and
the set-group-ID bit is set.
T If the character is part of the other permissions and
the file is
not executable or the directory is not searchable by
others, and
the ``sticky'' (S_ISVTX) bit is set.
s If the character is part of the owner permissions and
the file is
executable or the directory searchable by the owner,
and the setuser-ID
bit is set.
s If the character is part of the group permissions and
the file is
executable or the directory searchable by the group,
and the setgroup-ID
bit is set.
t If the character is part of the other permissions and
the file is
executable or the directory searchable by others, and
the
``sticky'' (S_ISVTX) bit is set.
x The file is executable or the directory is searchable.
- None of the above apply.
The last character is a plus sign (`+') if there are any alternate or additional
access control methods associated with the inode,
otherwise it
will be a space.
The strmode() function always returns 0.
chmod(1), find(1), stat(2), getmode(3), setmode(3)
The strmode() function first appeared in 4.4BSD.
OpenBSD 3.6 July 28, 1994
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