Operating Systems Which symbolic Unix filesystem permissions (i.e., as shown in
ID: 3583781 • Letter: O
Question
Operating Systems
Which symbolic Unix filesystem permissions (i.e., as shown in the leftmost column when running ls -l) correspond to the octal mode 644?
-r-sr-xr-x
-r-xr--r--
-rw-r--r--
-rwxr-xr-x
-r--------
Suppose that a programmer has installed the Java SDK onto a Windows machine, but when attempting to run javac from the command line, receives an error. Which command is most likely to resolve the problem?
export PATH="C:Program FilesJavajdk1.8.0_31in:$PATH"
dir /s c:javac.exe
which javac
alias javac="C:Program FilesJavajdk1.8.0_31injavac.exe"
set PATH=C:Program FilesJavajdk1.8.0_31in;%PATH%
A programmer compiles a C program on Linux using the command gcc -o myprog myprog.c and receives no errors, but upon running it by typing myprog, receives an error indicating that the myprog command is not found. What is the most likely problem and its solution?
_________________________________________________________________________
Which Unix utility would be the most useful in replacing all occurrences of the string “2014” in a file with the new string “2015” very quickly?
sed
patch
tr
date
m4
Which Unix utility would be most useful in removing all of the comments from an HTML file?
Note: HTML comments are multi-line, begin with <!-- and end with -->, and do not nest.
pr
sed
cut
awk
expr
On which operating system are wildcard characters, e.g. *, expanded only after they are received by a program executed at the command line, rather than by the shell prior to launching the program?
Android
Solaris
Linux
Mac OS X
Windows
Which description of the term “virtual memory” is most technically precise and accurate?
Each process running on the machine has its own page table, allowing the processor’s memory management unit to translate addresses
Disk space is used as memory once physical memory is exhausted
Recently-used disk files are buffered in memory for quick access
Memory is written to disk as part of hibernation so that it persists across power loss
Each virtual machine running on the system has a dedicated allotment of memory
Explanation / Answer
Which symbolic Unix filesystem permissions (i.e., as shown in the leftmost column when running ls -l) correspond to the octal mode 644?
Below permission mode is equvalant to octal 644. Because read valued 4 and write valued 2.
-rw-r--r--
Suppose that a programmer has installed the Java SDK onto a Windows machine, but when attempting to run javac from the command line, receives an error. Which command is most likely to resolve the problem?
Below command iwill solve the issue. It will add the path of javac to the PATH variable. alias and export are UNIX utility.
set PATH=C:Program FilesJavajdk1.8.0_31in;%PATH%
A programmer compiles a C program on Linux using the command gcc -o myprog myprog.c and receives no errors, but upon running it by typing myprog, receives an error indicating that the myprog command is not found. What is the most likely problem and its solution?
Answer: The parameter '-o' tells the GCC that instead of displaying the output of compilation process it needs to be stored into the file named just after the parameter 'o'. So, at the very beginning of the compilatio process GCC creates a file named myprog and starts storing compilation outputs into it. At executable generation phase after the compilation the executable myprog unable to generate as there is a file already exist as same name. That is why myprog can not be run as it is just a text file.
Which Unix utility would be the most useful in replacing all occurrences of the string “2014” in a file with the new string “2015” very quickly?
Answer: The most useful utility for this perpose would be 'tr'. Though sed can be used also but tr is much less complex.
Which Unix utility would be most useful in removing all of the comments from an HTML file?
Answer: Unix utility would be most useful in removing all of the comments from an HTML file would be sed.
On which operating system are wildcard characters, e.g. *, expanded only after they are received by a program executed at the command line, rather than by the shell prior to launching the program?
Answer: Windows
Which description of the term “virtual memory” is most technically precise and accurate?
Answer: Below description of the term “virtual memory” is most technically precise and accurate
Disk space is used as memory once physical memory is exhausted
Related Questions
Navigate
Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.