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Full Discussion: Kernel module - How to test if file doesn't exist
Top Forums Programming Kernel module - How to test if file doesn't exist Post 302501431 by fpmurphy on Thursday 3rd of March 2011 01:41:07 PM
Old 03-03-2011
This should work for you.
Code:
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/fs.h>
#include <linux/err.h>
#include <linux/errno.h>
#include <linux/file.h>
#include <linux/fcntl.h>
#include <linux/uaccess.h>

MODULE_LICENSE("GPL");
MODULE_AUTHOR("Chris <chris@example.com>");
MODULE_DESCRIPTION("Demo kernel driver");

void openFile(void) {
    struct file *fp = (struct file *) NULL;

    fp = filp_open("/home/chris/Test/testt", O_RDONLY, 0);
    if (IS_ERR(fp) || fp == NULL) {
        printk(KERN_ALERT "ERROR: filp_open\n");
        return;
    }
    if (fp->f_dentry == NULL) {
        printk(KERN_INFO "ERROR: dentry\n");
        return;
    }
    printk(KERN_INFO "FILENAME: %s\n", fp->f_dentry->d_name.name);
}

static int __init testIntro(void) {
    printk(KERN_INFO "elfStart\n");
    openFile();
    return 0;
}

static void __exit testOutro(void) {
    printk(KERN_INFO "Closing down\n");
}

From this you should be able to figure out what is wrong with your code.
These 3 Users Gave Thanks to fpmurphy For This Post:
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LEARN ABOUT MOJAVE

ibtl

ibtl(7D)							      Devices								  ibtl(7D)

NAME

       ibtl - Solaris InfiniBand Transport Layer

DESCRIPTION

       InfiniBand (IB) is an I/O technology based on switched fabrics. The Solaris InfiniBand Transport Layer (IBTL) is a Solaris kernel misc mod-
       ule and adheres to the IB Architecture Version 1.1 specification and provides a transport layer abstraction to IB client drivers.

       IBTL implements the programming interfaces for the Solaris InfiniBand Transport Framework (IBTF), consisting of the  IB	Channel  Interface
       (CI) and the IB Transport Interface (TI).

       The  CI	consists  of  Host  Channel Adapters (HCAs) and HCA drivers. A host is attached to the IB fabric through the CI layer. The Solaris
       InfiniBand CI is Sun's API rendering of the InfiniBand Architecture (IBTA) "verbs" specification.

       The Solaris InfiniBand TI is the kernel service driver interface into the Solaris InfiniBand Transport Framework. It provides transport and
       communications setup programming interfaces for Unreliable Datagram (UD) and Reliable Connected (RC) transport types only.

FILES

       /kernel/misc/ibtl

	   32-bit x86 ELF kernel misc module

       /kernel/misc/amd64/ibtl

	   64-bit x86 ELF kernel misc module

       /kernel/misc/sparcv9/ibtl

	   64-bit SPARC ELF kernel module

ATTRIBUTES

       See attributes(5) for a description of the following attribute:

       +-----------------------------+-----------------------------+
       |ATTRIBUTE TYPE		     |ATTRIBUTE VALUE		   |
       +-----------------------------+-----------------------------+
       |Interface Stability	     |Consolidation Private	   |
       +-----------------------------+-----------------------------+
       |Availability		     |SUNWhea, SUNWib		   |
       +-----------------------------+-----------------------------+

SEE ALSO

       attributes(5), ib(7D), ibcm(7D), ibdm(7D)

       InfiniBand Architecture Specification, Volume 1: Release 1.1

SunOS 5.10							    9 Oct 2004								  ibtl(7D)
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