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May 22, 2025 · Single UNIX Specification- “The Standard” The Single UNIX Specification is the standard in which the core interfaces of a UNIX OS are measured. The UNIX standard …
What does the line "#!/bin/sh" mean in a UNIX shell script?
Sep 10, 2011 · 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 …
linux - Explaining the 'find -mtime' command - Stack Overflow
Sep 1, 2014 · The POSIX specification for find says: -mtime n The primary shall evaluate as true if the file modification time subtracted from the initialization time, divided by 86400 (with any …
What are the special dollar sign shell variables? - Stack Overflow
Sep 14, 2012 · In Bash, there appear to be several variables which hold special, consistently-meaning values. For instance, ./myprogram &; echo $! will return the PID of the process …
unix - what does '$?' mean in a shell script? - Stack Overflow
Oct 5, 2012 · I came across a shell script that contains a statement like, if [ $val -eq $? ] What does $? mean here?
unix - How to check permissions of a specific directory ... - Stack ...
I know that using ls -l "directory/directory/filename" tells me the permissions of a file. How do I do the same on a directory? I could obviously use ls -l on the directory higher in the hierarchy...
unix - How to get PID of process by specifying process name and …
Jul 3, 2013 · pgrep -x <process_name> | xargs kill -9 (incidentally, for this specific use case, might as well do pkill -9 -x <process_name>, but the question asked how to get the PID in general) …
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How to check if $? is not equal to zero in unix shell scripting?
How to check if $? is not equal to zero in unix shell scripting? Asked 12 years, 7 months ago Modified 3 years, 7 months ago Viewed 356k times
bash - How can I split a large text file into smaller files with an ...
I've got a large (by number of lines) plain text file that I'd like to split into smaller files, also by number of lines. So if my file has around 2M lines, I'd like to split it up into 10 files t...