awk passing variables
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From: Stu on 7 Jul 2010 13:29 I want to parse HH:MM:SS with AWK. I know I can do something like this (see below) and this will put my values into variables, which I can use in the shell. But it also involves invoking awk 3 times, which is wasteful. cpu_hh=$(echo $cpu_time | $AWK -F':' ' { print $1 } ') cpu_mm=$(echo $cpu_time | $AWK -F':' ' { print $2 } ') cpu_sec=$(echo $cpu_time | $AWK -F':' ' { print $3 } ') can somebody show me an example of how I can pass a variable into awk (in this case I am assuming I have to initialize it as an array set -A array before I pass it into awk?), use the split command, and have the values available in my variable I passed in Ie arrary[1], array[2], array[3] so I can access the variable outside of AWK but within my script. Thanks to all who answer this post
From: pk on 7 Jul 2010 13:38 On Wed, 7 Jul 2010 10:29:10 -0700 (PDT) Stu <beefstu350(a)hotmail.com> wrote: > I want to parse HH:MM:SS with AWK. > > I know I can do something like this (see below) and this will put my > values into > variables, which I can use in the shell. But it also involves invoking > awk 3 times, > which is wasteful. > > cpu_hh=$(echo $cpu_time | $AWK -F':' ' { print $1 } ') > cpu_mm=$(echo $cpu_time | $AWK -F':' ' { print $2 } ') > cpu_sec=$(echo $cpu_time | $AWK -F':' ' { print $3 } ') > > can somebody show me an example of how I can pass a variable into awk > (in this case I am assuming I have to initialize it as an array set -A > array before > I pass it into awk?), use the split command, and have the values > available in my > variable I passed in Ie arrary[1], array[2], array[3] so I can > access the variable > outside of AWK but within my script. You don't need awk at all. With bash, you can do IFS=\: read -r cpu_hh cpu_mm cpu_sec <<<"$cpu_time"
From: Janis Papanagnou on 7 Jul 2010 13:53 On 07/07/10 19:29, Stu wrote: > I want to parse HH:MM:SS with AWK. > > I know I can do something like this (see below) and this will put my > values into > variables, which I can use in the shell. But it also involves invoking > awk 3 times, > which is wasteful. > > cpu_hh=$(echo $cpu_time | $AWK -F':' ' { print $1 } ') > cpu_mm=$(echo $cpu_time | $AWK -F':' ' { print $2 } ') > cpu_sec=$(echo $cpu_time | $AWK -F':' ' { print $3 } ') > > can somebody show me an example of how I can pass a variable into awk > (in this case I am assuming I have to initialize it as an array set -A > array before > I pass it into awk?), use the split command, and have the values > available in my > variable I passed in Ie arrary[1], array[2], array[3] so I can > access the variable > outside of AWK but within my script. > > Thanks to all who answer this post Are you ask for something like... cpu_time=23:12:56 x=$( echo $cpu_time | awk -F: '{print "cpu_hh="$1" cpu_mm="$2" cpu_sec="$3}' ) eval $x echo $cpu_hh echo $cpu_mm echo $cpu_sec Or maybe a shell only version... (in ksh, zsh, but not in bash) echo $cpu_time | IFS=: read cpu_hh cpu_mm cpu_sec echo $cpu_hh echo $cpu_mm echo $cpu_sec The same in bash... echo $cpu_time | { IFS=: read cpu_hh cpu_mm cpu_sec echo $cpu_hh echo $cpu_mm echo $cpu_sec } Janis
From: Janis Papanagnou on 7 Jul 2010 13:57 On 07/07/10 19:38, pk wrote: > On Wed, 7 Jul 2010 10:29:10 -0700 (PDT) > Stu <beefstu350(a)hotmail.com> wrote: > >> I want to parse HH:MM:SS with AWK. >> >> I know I can do something like this (see below) and this will put my >> values into >> variables, which I can use in the shell. But it also involves invoking >> awk 3 times, >> which is wasteful. >> >> cpu_hh=$(echo $cpu_time | $AWK -F':' ' { print $1 } ') >> cpu_mm=$(echo $cpu_time | $AWK -F':' ' { print $2 } ') >> cpu_sec=$(echo $cpu_time | $AWK -F':' ' { print $3 } ') >> >> can somebody show me an example of how I can pass a variable into awk >> (in this case I am assuming I have to initialize it as an array set -A >> array before >> I pass it into awk?), use the split command, and have the values >> available in my >> variable I passed in Ie arrary[1], array[2], array[3] so I can >> access the variable >> outside of AWK but within my script. > > You don't need awk at all. With bash, you can do > > IFS=\: read -r cpu_hh cpu_mm cpu_sec <<<"$cpu_time" > You can do that also in other shells, like ksh and zsh, BTW. (But I think <<< is non standard.) Janis
From: Ben Bacarisse on 7 Jul 2010 13:57
Stu <beefstu350(a)hotmail.com> writes: > I want to parse HH:MM:SS with AWK. > > I know I can do something like this (see below) and this will put my > values into > variables, which I can use in the shell. But it also involves invoking > awk 3 times, > which is wasteful. > > cpu_hh=$(echo $cpu_time | $AWK -F':' ' { print $1 } ') > cpu_mm=$(echo $cpu_time | $AWK -F':' ' { print $2 } ') > cpu_sec=$(echo $cpu_time | $AWK -F':' ' { print $3 } ') > > can somebody show me an example of how I can pass a variable into awk > (in this case I am assuming I have to initialize it as an array set -A > array before > I pass it into awk?), use the split command, and have the values > available in my > variable I passed in Ie arrary[1], array[2], array[3] so I can > access the variable > outside of AWK but within my script. I think you are asking the wrong question. Why must you use awk? You can get the result directly into shell variables in lots of ways that don't use awk. For example IFS=':' read cpu_hh cpu_mm cpu_ss and provide the time as an input. You could also, in bash, use an array: cpu=($(tr ':' ' ' <<<$cpu_time)) to get ${cpu[0]} etc. If you don't want to run even tr, use a function: function split { IFS=':' set "$1" echo "$1" "$2" "$3" } cpu=($(split "$cpu_time")) Variations on this scheme could provide you with the components one at a time. In short, there are lots of ways that are probably better than using awk. Which is best probably depends on where the data is coming from and where it will eventually go. In some cases, we might go full circle and decide that awk is the best option if the data comes from a multi-line file with lot of times in it. -- Ben. |