REVPATH(1) General Commands Manual REVPATH(1)NAME
revpath - generate a relative path that can be used to undo a change-directory
SYNOPSIS
revpath path
DESCRIPTION
The revpath program prints out a relative path that is the ``reverse'' or ``inverse'' of path. Start with two directories top and bottom,
with the latter below the former, and path is the location of bottom relative to top. The output of revpath is the location of top rela-
tive to bottom. The resulting path contains a trailing `/' character when the result is non-trivial. If path is equivalent to `.', the
resulting output is empty. If path is invalid in some way (e.g., doesn't represent the path to a subdirectory) the output is also empty
and no error messages are ever generated.
DIAGNOSTICS
There are no diagnostics. Error conditions are silently ignored, and the exit status is always 0.
BUGS
It isn't possible to reverse arbitrary relative paths. If any path element between the two end points of path is a symbolic link, the
results will probably be incorrect.
X Version 11 imake 1.0.5 REVPATH(1)
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resolvepath(2) System Calls resolvepath(2)NAME
resolvepath - resolve all symbolic links of a path name
SYNOPSIS
#include <unistd.h>
int resolvepath(const char *path, char *buf, size_t bufsiz);
DESCRIPTION
The resolvepath() function fully resolves all symbolic links in the path name path into a resulting path name free of symbolic links and
places the resulting path name in the buffer buf which has size bufsiz. The resulting path name names the same file or directory as the
original path name. All ``.'' components are eliminated and every non-leading ``..'' component is eliminated together with its preceding
directory component. If leading ``..'' components reach to the root directory, they are replaced by ``/''. If the number of bytes in the
resulting path name is less than bufsiz, the contents of the remainder of buf are unspecified.
RETURN VALUES
Upon successful completion, resolvepath() returns the count of bytes placed in the buffer. Otherwise, it returns -1, leaves the buffer
unchanged, and sets errno to indicate the error.
ERRORS
The resolvepath() function will fail if:
EACCES Search permission is denied for a component of the path prefix of path or for a path prefix component resulting
from the resolution of a symbolic link.
EFAULT The path or buf argument points to an illegal address.
EIO An I/O error occurred while reading from the file system.
ENOENT The path argument is an empty string or a component of path or a path name component produced by resolving a sym-
bolic link does not name an existing file.
ELOOP Too many symbolic links were encountered in resolving path.
ENAMETOOLONG The length of path exceeds PATH_MAX, or a path name component is longer than NAME_MAX. Path name resolution of a
symbolic link produced an intermediate result whose length exceeds PATH_MAX or a component whose length exceeds
NAME_MAX.
ENOTDIR A component of the path prefix of path or of a path prefix component resulting from the resolution of a symbolic
link is not a directory.
USAGE
No more than PATH_MAX bytes will be placed in the buffer. Applications should not assume that the returned contents of the buffer are null-
terminated.
SEE ALSO readlink(2), realpath(3C)SunOS 5.10 12 May 1997 resolvepath(2)
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