bash - Unix sh Script confusion -
bash - Unix sh Script confusion -
i have script 1 of professors college gave modify cannot seem figure out does. can help me understand bit better?
for grep $i; done
from can gather greps value of variable i, file or directory. not familiar how command comes play. appreciate tips offer.
look
isn't command, it's first parameter grep
. search word look
in file named $i
. (grep
not search folders unless pass in -r
in grep -r $i
.)
the confusing bit for i
comes in words
specified, for in 1 2 three
run commands between do
, done
3 times: 1 time variable i
= "one", 1 time i
= "two", , 1 time i
= "three". however, bash manual explains if in
isn't specified:
if ‘in words’ not present, command executes commands 1 time each positional parameter set, if ‘in "$@"’ had been specified [...].
so, in short, if script in file named foo.sh
, calling foo.sh file1 file2
word look
in files "file1" , "file2".
bash unix
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