Sed inside an awk statement

Question

I'd like to perform a series of sed commands on lines of a file roster.txt only beginning with a keyword. For example:

Employee : Kiara 20 [email protected]
Employee : Connor 25 [email protected]
Employee : Dylan 30 [email protected]

Becomes:

Employee : Kiara_20_hoursat8dot25
Employee : Connor_25_hoursat8dot00
Employee : Dylan_30_hoursat9dot00

I know the sed commands to make the changes I just wanted a way to peform them on lines starting with "employee". Maybe

awk '$1 == "Employee" {sed -i -e 's/\./dot/g' roster.txt}' roster.txt

Answer 1

$ cat roster.txt
foo : [email protected]
Employee : Kiara 20 [email protected]
Employee : Connor 25 [email protected]
Employee : Dylan 30 [email protected]

$ awk 'BEGIN{FS=OFS=" : "} $1=="Employee"{gsub(/ /,"_",$2); gsub(/@/,"at",$2); gsub(/\./,"dot",$2)} 1' roster.txt
foo : [email protected]
Employee : Kiara_20_hoursat8dot25
Employee : Connor_25_hoursat8dot00
Employee : Dylan_30_hoursat9dot00

awk supports substitution commands as well - sub to replace first occurrence and gsub to replace all occurrences. Also allows to change only specific field

• BEGIN{FS=OFS=" : "} use : as input/output field separator
• gsub(/ /,"_",$2) replace all spaces with _ only for second field
• Similarly other substitutions as required
• 1 at end of command is idiomatic way to print the line, includes any changes made
• See also awk save modifications in place