The UNIX® Standard | www. opengroup. org The Single UNIX Specification is the standard in which the core interfaces of a UNIX OS are measured The UNIX standard includes a rich feature set, and its core volumes are simultaneously the IEEE Portable Operating System Interface (POSIX) standard and the ISO IEC 9945 standard
unix - How to check permissions of a specific directory . . . - Stack . . . In GNU Linux, try to use ls, namei, getfacl, stat For Dir [flying@lempstacker ~]$ ls -ldh tmp drwxrwxrwt 23 root root 4 0K Nov 8 15:41 tmp [flying@lempstacker ~]$ namei -l tmp f: tmp dr-xr-xr-x root root drwxrwxrwt root root tmp [flying@lempstacker ~]$ getfacl tmp getfacl: Removing leading ' ' from absolute path names # file: tmp # owner: root # group: root # flags: --t user::rwx
What does the line #! bin sh mean in a UNIX shell script? When you try to execute a program in unix (one with the executable bit set), the operating system will look at the first few bytes of the file These form the so-called "magic number", which can be used to decide the format of the program and how to execute it #! corresponds to the magic number 0x2321 (look it up in an ascii table)
unix - How to use echo command to print out content of a text file . . . you could use echo command with cat as command substitution However, it will replace CR or return (unix: \n) with spaces: $ echo $(cat names txt) Homer Marge Bart Lisa Maggie Could be an interesting feature if you want to pipe to further data processing though E g replacing spaces with sed command
bash - How can I split a large text file into smaller files with an . . . As an aside, OS X users should make sure their file contains LINUX or UNIX-style Line breaks End-Of-Line indicators (LF) instead of MAC OS X - style end-of-line indicators (CR) - the split and csplit commands will not work if your like breaks are Carriage Returns instead of LineFeeds
unix - How to attach a file using mail command on Linux . . . - Stack . . . The following is a decent solution across Unix Linux installations, that does not rely on any unusual program features This supports a multi-line message body, multiple attachments, and all the other typical features of mailx Unfortunately, it does not fit on a single line