Bash: Difference between revisions
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==Swapping stdin and stdout == | == Swapping stdin and stdout == | ||
command 3>&1 1>&2 2>&3 | command 3>&1 1>&2 2>&3 | ||
== extracting vars from strings == | |||
<pre> | |||
#!/usr/bin/env bash | |||
str1="the value of var1=test, the value of var2=testing, the final value of var3=testing1" | |||
re='(^|[[:space:]])([[:alpha:]][[:alnum:]]*)=([^, ]+)([, ]|$)(.*)' | |||
remaining=$str1 | |||
while [[ $remaining =~ $re ]]; do | |||
varname=${BASH_REMATCH[2]} | |||
value=${BASH_REMATCH[3]} | |||
remaining=${BASH_REMATCH[5]} | |||
printf -v "$varname" %s "$value" | |||
done | |||
# show current values to demonstrate that variables were really assigned | |||
declare -p var1 var2 var3 | |||
</pre> | |||
== Also See == | == Also See == | ||
Revision as of 15:35, 24 December 2019
Swapping stdin and stdout
command 3>&1 1>&2 2>&3
extracting vars from strings
#!/usr/bin/env bash
str1="the value of var1=test, the value of var2=testing, the final value of var3=testing1"
re='(^|[[:space:]])([[:alpha:]][[:alnum:]]*)=([^, ]+)([, ]|$)(.*)'
remaining=$str1
while [[ $remaining =~ $re ]]; do
varname=${BASH_REMATCH[2]}
value=${BASH_REMATCH[3]}
remaining=${BASH_REMATCH[5]}
printf -v "$varname" %s "$value"
done
# show current values to demonstrate that variables were really assigned
declare -p var1 var2 var3
