media_findname(3VOLMGT) Volume Management Library Functions media_findname(3VOLMGT)
NAME
media_findname - convert a supplied name into an absolute pathname that can be used to access removable media
SYNOPSIS
cc [ flag ... ] file ... -lvolmgt [ library ... ]
#include <volmgt.h>
char *media_findname(char *start);
DESCRIPTION
media_findname() converts the supplied start string into an absolute pathname that can then be used to access a particular piece of media.
The start parameter can be one of the following types of specifications:
/dev/... An absolute pathname in /dev, such as /dev/rdiskette0, in which case a copy of that string is returned (see NOTES
on this page).
/vol/... An absolute Volume Management pathname, such as /vol/dev/aliases/floppy0 or /vol/dsk/fred. If this supplied path-
name is not a symbolic link, then a copy of that pathname is returned. If the supplied pathname is a symbolic link
then it is dereferenced and a copy of that dereferenced pathname is returned.
volume_name The Volume Management volume name for a particular volume, such as fred (see fdformat(1) for a description of how
to label floppies). In this case a pathname in the Volume Management namespace is returned.
volmgt_symname The Volume Management symbolic name for a device, such as floppy0 or cdrom2 (see volfs(7FS) for more information on
Volume Management symbolic names), in which case a pathname in the Volume Management namespace is returned.
media_type The Volume Management generic media type name. For example, floppy or cdrom. In this case media_findname() looks
for the first piece of media that matches that media type, starting at 0 (zero) and continuing on until a match is
found (or some fairly large maximum number is reached). In this case, if a match is found, a copy of the pathname
to the volume found is returned.
RETURN VALUES
Upon successful completion media_findname() returns a pointer to the pathname found. In the case of an error a null pointer is returned.
ERRORS
For cases where the supplied start parameter is an absolute pathname, media_findname() can fail, returning a null string pointer, if an
lstat(2) of that supplied pathname fails. Also, if the supplied absolute pathname is a symbolic link, media_findname() can fail if a read-
link(2) of that symbolic link fails, or if a stat(2) of the pathname pointed to by that symbolic link fails, or if any of the following is
true:
ENXIO The specified absolute pathname was not a character special device, and it was not a directory with a character special
device in it.
EXAMPLES
Example 1: Sample programs of the media_findname() function.
The following example attempts to find what the Volume Management pathname is to a piece of media called fred. Notice that a
volmgt_check() is done first (see the NOTES section on this page).
(void) volmgt_check(NULL);
if ((nm = media_findname("fred")) != NULL) {
(void) printf("media named "fred" is at "%s"
", nm);
} else {
(void) printf("media named "fred" not found
");
}
This example looks for whatever volume is in the first floppy drive, letting media_findname() call volmgt_check() if and only if no floppy
is currently known to be the first floppy drive.
if ((nm = media_findname("floppy0")) != NULL) {
(void) printf("path to floppy0 is "%s"
", nm);
} else {
(void) printf("nothing in floppy0
");
}
ATTRIBUTES
See attributes(5) for descriptions of the following attributes:
+-----------------------------+-----------------------------+
| ATTRIBUTE TYPE | ATTRIBUTE VALUE |
+-----------------------------+-----------------------------+
|MT-Level |MT-Unsafe |
+-----------------------------+-----------------------------+
SEE ALSO
cc(1B), fdformat(1), vold(1M), lstat(2), readlink(2), stat(2), free(3C), malloc(3C), volmgt_check(3VOLMGT), volmgt_inuse(3VOLMGT),
volmgt_root(3VOLMGT), volmgt_running(3VOLMGT), volmgt_symname(3VOLMGT), attributes(5), volfs(7FS)
NOTES
If media_findname() cannot find a match for the supplied name, it performs a volmgt_check(3VOLMGT) and tries again, so it can be more effi-
cient to perform volmgt_check() before calling media_findname().
Upon success media_findname() returns a pointer to string which has been allocated; this should be freed when no longer in use (see
free(3C)).
SunOS 5.10 31 Dec 1996 media_findname(3VOLMGT)