POSIX stands for Portable Operating System Interface. It’s a family of standards specified by IEEE for maintaining compatibility among operating systems.
Questions tagged [posix]
85 questions
65
votes
5 answers
less is more? Is more less? I'm so confused
When I first heard their names, I got really confused when I tried to guess what these tools might do, I thought I'd misheard something.
What's the difference between more and less, i.e. why should I choose one over the other?
They both seem to…
user541686
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62
votes
9 answers
Alternative to the tee command without STDOUT
I'm using | sudo tee FILENAME to be able to write or append to a file for which superuser permissions are required quite often.
Although I understand why it is helpful in some situation, that tee also sends its input to STDOUT again, I never ever…
aef
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61
votes
2 answers
What is the difference between `/etc/environment` and `/etc/profile`?
I understand that the former is loaded prior to the latter, but what is the difference in their purpose and otherwise? Are there any good reasons I should set some variables in one and not the other?
What little I understand is that /etc/environment…
Armen Michaeli
- 2,722
53
votes
3 answers
How to delete a file with a weird name?
I wrote a program that uses POSIX memory-mapping function (mmap)
The program takes a file (a.dat) and memory-maps it for reading/writing.
Due to errors in the program, every time I run the program a file with some weird names (e.g.,…
A. K.
- 665
35
votes
5 answers
bash pipe construct to prepend something to the stdoutput of previous command
I want to use sendmail to send me stuff and want to do it in a oneliner.
echo "mail content" | sendmail emailataddres.com
Sends it without subject.
The subject line must come before the Mail content,
so I am looking for something along the lines…
AndreasT
- 769
29
votes
3 answers
What's the difference between SIGKILL and SIGSTOP?
The manual describes SIGKILL and SIGSTOP like this:
SIGKILL 9 Term Kill signal
SIGTERM 15 Term Termination signal
SIGSTOP 17,19,23 Term Stop the process
and states:
The signals SIGKILL and SIGSTOP…
qdii
- 1,107
28
votes
3 answers
Why is NTFS case sensitive?
I personally thought that NTFS was case insensitive, since you can type cmd, CMD, cMd or even CmD and still get the command prompt. However, why is it that during a CHKDSK x: /f /r, sometimes it fixes capitalization in some files? If it didn't care…
Canadian Luke
- 24,640
19
votes
2 answers
What does it mean to have a POSIX-compliant operating system?
What does it mean if the operating system is said to be POSIX-compliant?
Sergey
- 1,755
17
votes
1 answer
SUID bit on directories
In Linux there are SUID, SGID, and sticky bits for directory permissions.
I am absolutely clear about the sticky and SGID bit on files or folders.
But what happens if I apply SUID bit on a directory?
For example, if I apply a SGID bit on a file, a…
TheMAn
- 183
13
votes
5 answers
13
votes
6 answers
Standard way to duplicate a file's permissions
I am trying to find a standard POSIX way to duplicate one file's permissions to another file. On a GNU system this is easy:
[alexmchale@bullfrog ~]$ ls -l hardcopy.*
-rw-r--r-- 1 alexmchale users 2972 Jul 8 20:40 hardcopy.1
---------- 1 alexmchale…
Alex
- 735
9
votes
3 answers
does PATH search include symlinks?
The POSIX shell standard says on this site
http://pubs.opengroup.org/onlinepubs/9699919799/
about how shells use PATH to look for executables:
"The list shall be searched from beginning to end, applying the filename to each prefix, until an…
user322908
- 819
8
votes
2 answers
Script to convert ext4 filenames to NTFS
ext4 allows certain chars in filenames which NTFS doesn't. Is there a script to replace those chars in filenames?
ncvncncvncv
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8
votes
1 answer
How to convert a Windows path (with backslashes) to Unix format on Babun/Cygwin
I'm using Windows and writing shell scripts to run on Babun (a POSIX api).
I need to read a path from an environment variable, $USERPROFILE, and convert it to unix style (replace \ by /, c:\ by /c/) so I can use it later in the script.
The problem…
Victor Basso
- 593
7
votes
2 answers
discover the directory that prevents a file from being read in linux
i'm getting a permission denied for a user in a really long path.
$ sudo sudo -u user cat /l/o/n/g/path/file
Permission denied
i'm pretty sure path and file have permissions for that user. Is there any easy way to find which of the other…
gcb
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