12-17-2008
Sorry, please add the . char after PATH_MAX.
10 More Discussions You Might Find Interesting
1. UNIX for Dummies Questions & Answers
Hi folks,
Can anybody tell me whether there is any limit on the file name length and directory name length in UNIX. (4 Replies)
Discussion started by: rkkiran
4 Replies
2. UNIX for Dummies Questions & Answers
What is the maximum size of a command which can be given in telnet command prompt in unixfor Korn shell? (2 Replies)
Discussion started by: miltony
2 Replies
3. UNIX for Dummies Questions & Answers
What is the maximum size of a command which can be given in telnet command prompt in unix? (2 Replies)
Discussion started by: miltony
2 Replies
4. UNIX for Dummies Questions & Answers
Hi All,
I didn't find any thread that match this question so I hope it's not redundant. I am totally new to Unix. I want to know what is the maximum length of the os-commandline in Unix. Will it cause any problem if I run any application whose total path length is much longer than 256... (2 Replies)
Discussion started by: kumardesai
2 Replies
5. Shell Programming and Scripting
what is the maximum length of a unix shell variable which can be can passed to plsql variable:( (1 Reply)
Discussion started by: alokjyotibal
1 Replies
6. UNIX for Dummies Questions & Answers
Hi,
I need to create a file of record length more than 300 characters.
But in my unix box, i am able to create a file only with a maximum of 256 characters per record.
Is there anyway i can create a file with more than 300 characters in this case?
Or How to increase the maximum record... (1 Reply)
Discussion started by: mahish20
1 Replies
7. Shell Programming and Scripting
Hi,
I wanted to know what is the maximum length of command which can be run on a bourne (sh) shell? Where can I find that information? Is it different for different OS flavors?
Please help.
Thanks,
Vineet (10 Replies)
Discussion started by: vineetd
10 Replies
8. Shell Programming and Scripting
Is there a maximum length for a shell script command? How can I detect that in my OS?
For example, if I have something like:
command A | command B | command C | awk '{print $1 $2 $3 $4 $5}'
then can we break the commands and also the arguments inside awk ?
Thanks (11 Replies)
Discussion started by: hbar
11 Replies
9. Programming
How can I change the maximum length of a programming line in fortran and C (specifically in fortran 77)?
Seems the default maximum length is 72 in fortran 77.
Thanks. (4 Replies)
Discussion started by: hbar
4 Replies
10. Shell Programming and Scripting
good friends days
I would love to know if I can help you know the length of a string
example:
cadena= "cual es mi largo"
echo "cadena : $cadena#
cadena :16 (7 Replies)
Discussion started by: tricampeon81
7 Replies
LEARN ABOUT REDHAT
realpath
REALPATH(3) Linux Programmer's Manual REALPATH(3)
NAME
realpath - return the canonicalized absolute pathname
SYNOPSIS
#include <limits.h>
#include <stdlib.h>
char *realpath(const char *path, char *resolved_path);
DESCRIPTION
realpath expands all symbolic links and resolves references to '/./', '/../' and extra '/' characters in the null terminated string named
by path and stores the canonicalized absolute pathname in the buffer of size PATH_MAX named by resolved_path. The resulting path will have
no symbolic link, '/./' or '/../' components.
RETURN VALUE
If there is no error, it returns a pointer to the resolved_path.
Otherwise it returns a NULL pointer, and the contents of the array resolved_path are undefined. The global variable errno is set to indi-
cate the error.
ERRORS
EACCES Read or search permission was denied for a component of the path prefix.
EINVAL Either path or resolved_path is NULL. (In libc5 this would just cause a segfault.)
EIO An I/O error occurred while reading from the file system.
ELOOP Too many symbolic links were encountered in translating the pathname.
ENAMETOOLONG
A component of a path name exceeded NAME_MAX characters, or an entire path name exceeded PATH_MAX characters.
ENOENT The named file does not exist.
ENOTDIR
A component of the path prefix is not a directory.
BUGS
The libc4 and libc5 implementation contains a buffer overflow (fixed in libc-5.4.13). Thus, suid programs like mount need a private ver-
sion.
The length of the output buffer should have been an additional parameter, especially since pathconf(3) warns that the result of pathconf()
may be huge and unsuitable for mallocing memory.
HISTORY
The realpath function first appeared in BSD 4.4, contributed by Jan-Simon Pendry. In Linux this function appears in libc 4.5.21.
CONFORMING TO
In BSD 4.4 and Solaris the limit on the pathname length is MAXPATHLEN (found in <sys/param.h>). The SUSv2 prescribes PATH_MAX and NAME_MAX,
as found in <limits.h> or provided by the pathconf() function. A typical source fragment would be
#ifdef PATH_MAX
path_max = PATH_MAX;
#else
path_max = pathconf (path, _PC_PATH_MAX);
if (path_max <= 0)
path_max = 4096;
#endif
The BSD 4.4, Linux and SUSv2 versions always return an absolute path name. Solaris may return a relative path name when the path argument
is relative. The prototype of realpath is given in <unistd.h> in libc4 and libc5, but in <stdlib.h> everywhere else.
SEE ALSO
readlink(2), getcwd(3), pathconf(3), sysconf(3)
1999-08-24 REALPATH(3)