Bash for

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Revision as of 23:57, 29 February 2016 by Ovidiu (talk | contribs) (→‎for and IFS)
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External

Internal

Overview

The for built-in command expand words, and execute commands once for each member in the resultant list, with i bound to the current member.

   for i in words; do commands; done

Alternatively, for:

   for i do commands; done

commands executes for each positional parameter (as if in "$@" had been specified.

Yes another alternative form:

    for (( i=0; i<${#names[@]}; i++ )); do
        local name=${names[${i}]}
        echo "${name}"
    done

Iterating through $1, $2, $3 ...

     for i do
         echo ${i}
     done

Iterating through a space separated list

    s="a b c"
    for i in ${s}
        do
            echo ${i}
        done

or

     s="a b c"
     for i in ${s}; do echo ${i}; done

Note the use of ";"

for and IFS

IFS