Thursday, October 22

Mntent.h

This element contains a pointer to a string describing the name of the special device from which the filesystem is mounted. This element points to a string describing the mount point of the filesystem. But since the kernel can support arbitrary filesystems it does not make much sense to give them symbolic names.

If one knows the symbol name one also knows the filesystem name. Nevertheless here follows the list of the symbols provided in mntent. This symbol expands to "ignore". The value is sometimes used in fstab files to make sure entries are not used without removing them. Expands to "nfs". Using this macro sometimes could make sense since it names the default NFS implementation, in case both version 2 and 3 are supported. This symbol expands to "swap". It names the special fstab entry which names one of the possibly multiple swap partitions.

The element contains a string describing the options used while mounting the filesystem. The mntent. Expands to "defaults". This option should be used alone since it indicates all values for the customizable values are chosen to be the default. Expands to "ro".

Expands to "rw". Expands to "suid". Expands to "nosuid". Expands to "noauto".GitHub is home to over 50 million developers working together to host and review code, manage projects, and build software together.

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community. Already on GitHub? Sign in to your account. I'm trying to build from source so that I can use this patch 2aa. I am on Debian Jessie. CredSSP support requires libgssglue, install the dependency or disable the feature using --disable-credssp.

I don't need smart card support so I configured again with. I installed libkrb5-dev, but when I run make, I don't see that being included on the linker line. Is there maybe another parameter I need to use on configure? Mark, just to make sure we're all on the same page - are you using the latest release 1. I was trying to build including this patch 2aa. The patch you are referring was committed to rdesktop onso any later version would include it. I think you're better off building with the latest 1.

Skip to content. Dismiss Join GitHub today GitHub is home to over 50 million developers working together to host and review code, manage projects, and build software together.

Sign up. New issue. Jump to bottom. Labels awaiting reply. Copy link Quote reply. Hi, I'm trying to build from source so that I can use this patch 2aa. Hi, Mark! One more hint: Use libkrb5-dev instead of libgsslue. Thanks for your help. I removed libgssglue and when I. I did check the libssl versions and they are the same as yours. Apologies for my ignorance Should I be doing something else?

Thanks, Mark.

w_getmntent() — Get information on mounted file systems

I see, thanks for clarifying! Gents, thanks very much.The mount function requests that a removable file system contained on the block special file identified by spec be mounted on the directory identified by dir.

The spec and dir arguments are pointers to path names.

mntent.h

After a successful call to mountall references to the file dir refer to the root directory on the mounted file system. The mounted file system is inserted into the kernel list of all mounted file systems. This list can be examined through the mounted file system table see mnttab 4. The fstype argument is the file system type name. The optlen argument specifies the length of the buffer.

On completion of the mount call, the options in effect for the mounted file system are returned in this buffer. The dataptr and datalen arguments describe a block of file system-specific binary data at address dataptr of length datalen. This is interpreted by file system-specific code within the operating system and its format depends on the file system type.

If a particular file system type does not require this data, dataptr and datalen should both be 0.

mntent.h

Mount a file system globally if the system is configured and booted as part of a cluster see clinfo 1M. Prevent programs that are marked set-user-ID or set-group-ID from executing see chmod 1. The optptr and optlen arguments describe a character buffer at address optptr of size optlen. When calling mountthe character buffer should contain a null-terminated string of options to be passed to the file system-specific code within the operating system.

On a successful return, the file system-specific code will return the list of options recognized. Unrecognized options are ignored. The format of the string is a list of option names separated by commas. Only strings defined in the "C" locale are supported. The buffer should be long enough to contain more options than were passed in, as the state of any default options that were not passed in the input option string may also be returned in the recognized options list that is returned.

Allow the file system to be mounted over an existing file system mounted on dirmaking the underlying file system inaccessible. If a mount is attempted on a pre-existing mount point without setting this flag, the mount will fail. Mount the file system for reading only.

This flag should also be specified for file systems that are incapable of writing for example, CDROM. Without this flag, writing is permitted according to individual file accessibility. Upon successful completion, 0 is returned.

Otherwise, -1 is returned and errno is set to indicate the error. The dir argument is currently mounted on, is someone's current working directory, or is otherwise busy; the device associated with spec is currently mounted; or there are no more mount table entries. The specdirfstypedataptror optptr argument points outside the allocated address space of the process.

The path argument points to a remote machine and the link to that machine is no longer active. The dir argument is not a directory, or a component of a path prefix is not a directory. The length of the option string to be returned in the optptr argument exceeds the size of the buffer specified by optlen. The mount function can be invoked only by processes with superuser privileges. Some flag bits set file system options that can also be passed in an option string.Today's Posts.

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The first version of the Submit Answer. The setmntent function opens the file system description file filename and returns a file pointer which can be used by getmntent. The argument type is the type of access required and can take the same values as the mode argument of fopen 3.

The getmntent function reads the next line from the file system description file fp and returns a pointer to a structure containing the broken out fields from a line in the file. The pointer points to a static area of memory which is overwritten by subsequent calls to getm- ntent. The addmntent function adds the mntent structure mnt to the end of the open file fp. The endmntent function closes the file system description file fp. The rou- tines addmntent and getmntent will convert from string representation to escaped representation and back.

The addmntent function returns 0 on success and 1 on failure. The endmntent function always returns 1. The hasmntopt function returns the address of the substring if a match is found and NULL otherwise. The prototype shown above is glibc-only. NOTES System V also has a getmntent function but the calling sequence differs, and the returned structure is different.

OpenSolaris Commands.

addmntent(3)

Advanced Search. Contact Us.The default mapping format is struct mnte when the eyecatcher field is unset. The positioning information should not be changed between calls. The mount mode of the file system. A flag field that specifies the mount mode and additional mount options: mntentfsaunmount. If all entries do not fit in the buffer supplied, multiple calls are required. If an entry together with its mount parameter will not fit in the buffer, the entry is returned without the mount parameter.

setmntent(3) [suse man page]

To assure that at least one entry, including the mount parameter, is returned, it is advisable to allocate space for at least two entries. A flag field that specifies the mount mode and additional mount options:. The pathname of the directory where the file system is mounted. This field ends with a NULL. The file-system-specific parameter specified on the mount function when the file system was mounted.

General description Gets information about all currently mounted file systems. The storage consists of a header and an entry table that correspond to one of the available mapping formats. Each entry in the entry table will contain information for a single mounted file system.

If size is zero, the total number of mount entries is returned. You can use this information to obtain a buffer large enough to hold all the information about all the entries. Use the new buffer on the subsequent call.

Three mapping formats available. If it is 0, then the setting of mntentfsnoautomove will be used. See mntentfsnoautomove below. If it is 1, then the file system is not a sysplex client. If it is 1 after the file system is mounted, it will not be moved automatically. If it is 0, then the file system will enforce security checks.

mntent.h

If it is 1, then the file system has been exported by DFS. If it is 1, then the file system is mounted as read-only. The name for the file system that performed the mount. If the value is zero, then no aggregate name is returned. A flag field that specifies the mount mode and additional mount options: mntentfsaunmount If it is 1 after the file system is mounted, the file system will be unmounted when a system leaves the sysplex.

Output: filesystem ZOS Parent topic: Library functions.The setmntent function opens the filesystem description file filename and returns a file pointer which can be used by getmntent. The argument type is the type of access required and can take the same values as the mode argument of fopen 3. The getmntent function reads the next line of the filesystem description file from stream and returns a pointer to a structure containing the broken out fields from a line in the file.

The pointer points to a static area of memory which is overwritten by subsequent calls to getmntent. The addmntent function adds the mntent structure mnt to the end of the open stream. The endmntent function closes the stream associated with the filesystem description file. The routines addmntent and getmntent will convert from string representation to escaped representation and back.

The hasmntopt function returns the address of the substring if a match is found and NULL otherwise. For an explanation of the terms used in this section, see attributes 7. The nonreentrant functions are from SunOS 4. The prototype shown above is glibc-only. System V also has a getmntent function but the calling sequence differs, and the returned structure is different.

This page is part of release 4. The addmntent function returns 0 on success and 1 on failure. The endmntent function always returns 1. NOTES System V also has a getmntent function but the calling sequence differs, and the returned structure is different.By using our site, you acknowledge that you have read and understand our Cookie PolicyPrivacy Policyand our Terms of Service. Stack Overflow for Teams is a private, secure spot for you and your coworkers to find and share information.

Very occasionally, the filesystem metadata on one of these drives gets corrupted for whatever reason ext4 journalling notwithstandingwhich can cause the ext4 filesystem drive to detect a problem and remount the partition as read-only, presumably as a precaution against cascading errors corrupting the drive further. Okay, fair enough; but what I'd like to do now is add a function to my program that can detect when the drive is in this remounted-read-only state, so that it can pro-actively notify the user that his drive is in trouble.

Attempting to write a file to the filesystem isn't good enough, because that could fail for other reasons, and also because I don't want to write to the filesystem if I don't have to. It seems like stat might be able to do it, but I can't see how. The getmntent family should meet your needs. The setmntent function opens the filesystem description file filename and returns a file pointer which can be used by getmntent. The argument type is the type of access required and can take the same values as the mode argument of fopen 3.

The getmntent function reads the next line of the filesystem description file from stream and returns a pointer to a structure containing the broken out fields from a line in the file. The pointer points to a static area of memory which is overwritten by subsequent calls to getmntent.

See and mount 8 for valid mount options. The easiest way to check that the filesystem of an open file for writing has become mounted read-only is to check the errno variable for EROFS error.

If you don't have the possibility of having a writable directory or file in that filesystem, you cannot get a portable way of checking if the filesystem has become read only more if it has become so due to device errors. But this is linux specific only. Learn more. Ask Question. Asked 3 years, 5 months ago. Active 3 years, 5 months ago. Viewed 2k times. Jeremy Friesner Jeremy Friesner The man page also notes that statvfs calls the linux syscall statfs to get this info now.

NominalAnimal I think your comment contains the answer I'm looking for; if you want to repost it as an Answer I'll mark it. Active Oldest Votes. The addmntent function adds the mntent structure mnt to the end of the open stream.

The endmntent function closes the stream associated with the filesystem description file. Andrew Henle Andrew Henle JeremyFriesner I don't know any easy way to programmatically determine if a filesystem has been remounted read-only because of a disk error other than trying to write to it. If that's a requirement you have to meet, you should probably test it somehow.

If you're lucky, the visible mount options will changes. Or you can ask another, follow-on question - somebody out there probably knows already. This is not a good solution while Nominal Animal 's comment statvfs or simlar is clean and better. To follow solution of getmntent and to address the question i. Luis Colorado Luis Colorado 6, 1 1 gold badge 8 8 silver badges 25 25 bronze badges.

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