A script refreshes the timestamps of log files but must never bring a missing file into existence. Type the short option for touch, including its leading dash, that suppresses the creation of files that do not already exist.
LPIC-1 Exam 101-500, objective 103. GNU and Unix commands medium
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Answer
Type the answer.
Accepted answers
-c--no-create
Case sensitive — Linux is, and grading LS as ls would teach a falsehood.
Why
touch has two jobs: it sets a file's access and modification times to the current time, and it creates the file as empty if it is absent. -c (--no-create) removes the second job, so a missing operand is skipped silently rather than created. The times can also be given explicitly with -d for a date string or -t for a [[CC]YY]MMDDhhmm[.ss] stamp, and -a or -m restricts the change to one of the two times.
Where this comes from
- Cited
- manual page touch(1)
Practise this
Reading one question is not practice. The trainer will draw a short set from objective 103 and space the ones you get wrong.
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