Your code will not work. /proc/pid/fd/0 is a link to the /dev/pts/6 file. $ echo ‘foobar’ > /dev/pts/6 $ echo ‘foobar’ > /proc/pid/fd/0 Since both the commands write to the terminal. This input goes to terminal and not to the process. It will work if stdin intially is a pipe. For example, test.py is : … Read more
The simplest way to map a set of pages from the kernel in your mmap method is to use the fault handler to map the pages. Basically you end up with something like: static int my_mmap(struct file *filp, struct vm_area_struct *vma) { vma->vm_ops = &my_vm_ops; return 0; } static const struct file_operations my_fops = { … Read more
This link contains a good checklist why core dumps are not generated: The core would have been larger than the current limit. You don’t have the necessary permissions to dump core (directory and file). Notice that core dumps are placed in the dumping process’ current directory which could be different from the parent process. Verify … Read more
Um, lets not forget sort –random-sort
On Ubuntu , it can be disabled with… echo 0 > /proc/sys/kernel/randomize_va_space On Windows, this post might be of some help… http://blog.didierstevens.com/2007/11/20/quickpost-another-funny-vista-trick-with-aslr/
iirc : cat filename.txt | awk ‘{ print $2 $4 }’ or, as mentioned in the comments : awk ‘{ print $2 $4 }’ filename.txt
With gzip files, you can simply concatenate the files together, like so: cat file1.gz file2.gz file3.gz > allfiles.gz Per the gzip RFC, A gzip file consists of a series of “members” (compressed data sets). […] The members simply appear one after another in the file, with no additional information before, between, or after them. Note … Read more
To answer your actual question, when a shell function is on the receiving end of a pipe, standard input is inherited by all commands in the function, but only commands that actually read form their standard input consume any data. For commands that run one after the other, later commands can only see what isn’t … Read more
Have a look at this. Starting with version 2.5, linux kernel introduced a new system call entry mechanism on Pentium II+ processors. Due to performance issues on Pentium IV processors with existing software interrupt method, an alternative system call entry mechanism was implemented using SYSENTER/SYSEXIT instructions available on Pentium II+ processors. This article explores this … Read more
from “man 1 passwd“: –stdin This option is used to indicate that passwd should read the new password from standard input, which can be a pipe. So in your case adduser “$1” echo “$2” | passwd “$1” –stdin [Update] a few issues were brought up in the comments: Your passwd command may not have a … Read more