DragonFly On-Line Manual Pages
REALPATH(3) DragonFly Library Functions Manual REALPATH(3)
realpath -- returns the canonicalized absolute pathname
Standard C Library (libc, -lc)
realpath(const char * restrict pathname, char * restrict resolved_path);
The realpath() function resolves all symbolic links, extra ``/'' charac-
ters and references to /./ and /../ in pathname, and copies the resulting
absolute pathname into the memory pointed to by resolved_path. The
resolved_path argument must point to a buffer capable of storing at least
PATH_MAX characters, or be NULL.
The realpath() function will resolve both absolute and relative paths and
return the absolute pathname corresponding to pathname. All components
of pathname must exist when realpath() is called, and all but the last
component must name either directories or symlinks pointing to the direc-
The realpath() function returns resolved_path on success. If the func-
tion was supplied NULL as resolved_path, and operation did not cause
errors, the returned value is a null-terminated string in a buffer allo-
cated by a call to malloc(3). If an error occurs, realpath() returns
NULL, and if resolved_path is not NULL, the array that it points to con-
tains the pathname which caused the problem.
The function realpath() may fail and set the external variable errno for
any of the errors specified for the library functions lstat(2),
readlink(2) and getcwd(3).
The realpath() function first appeared in 4.4BSD.
This implementation of realpath() differs slightly from the Solaris
implementation. The 4.4BSD version always returns absolute pathnames,
whereas the Solaris implementation will, under certain circumstances,
return a relative resolved_path when given a relative pathname.
DragonFly 4.3 March 18, 2015 DragonFly 4.3