awk gsub

Shell Programming and Scripting
1

Hi all
I want to do a simple substitution in awk but I am getting unexpected output. My function accepts a time and then prints out a validation message if the time is valid. However some times may include a : and i want to strip this out if it exists before i get to the validation. I have shown a small sample of my function below which is giving the unexpected output. When this function is called with 23:01 the first print time gives 23:01 but the second gives a 1. What i want is simply 2301.
Can anyone let me know what im doing wrong.

function getTime(time)
{
        print time;
        time = gsub(":","x",time);
        print time;
}

Thanks

2

The code i have posted contains an x as the substitution character. Ignore this as it is a typing error. My code uses "" as substitution character

3

man command help you.

       gsub(r, s [, t])        For each substring matching the regular expression r in the
                               string t, substitute the string s, and return the number of
                               substitutions.   If t is not supplied, use $0.  An & in the
                               replacement text is replaced with the text that  was  actu*
                               ally  matched.   Use  \& to get a literal &.  (This must be
                               typed as "\\&"; see GAWK: Effective AWK Programming  for  a
                               fuller  discussion  of the rules for &'s and backslashes in
                               the replacement text of sub(), gsub(), and gensub().)
4

Thank you
I Did look at the man page but it didn't register why I was getting a one.

5 
man awk

or

info awk

or
If awk is gawk, you can look at below page.
Gawk - GNU Project - Free Software Foundation (FSF)