Pode ser algo assim?
man -a intro | # awk grabs the header from each intro man page
awk '/INTRO/ { $1 = substr($1,7,1) # set $1 to x in INTRO(x)
$2 = "" # set $2 to nothing
sub(/INTRO\([0-9]\)/, "") # remove the string INTRO(x) from last field
print | "sort"
}'
Os resultados:
1 General Commands Manual
2 System Calls Manual
3 Library Functions Manual
5 File Formats Manual
7 Miscellaneous Information Manual
8 System Manager's Manual
9 Kernel Developer's Manual
Observe as seções ausentes.