Bash/Printf: Unterschied zwischen den Versionen
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Cbs (Diskussion | Beiträge) K (hat „Printf“ nach „Bash/Printf“ verschoben) |
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| − | ==repeated output== | + | == string escaping == |
| + | |||
| + | to 'bash'-escape a string use printf | ||
| + | |||
| + | <pre> | ||
| + | a=''\''"\;:#[]{}()|&^$@!?, .<>abc123' | ||
| + | printf -v var "%q" "$a" | ||
| + | echo "$var" | ||
| + | \'\"\\\;:#\[\]\{\}\(\)\|\&\^\$@\!\?\,\ .\<\>abc123 | ||
| + | </pre> | ||
| + | have fun! | ||
| + | |||
| + | |||
| + | == repeated output == | ||
| + | |||
if you want to format output e.g. by spaces do | if you want to format output e.g. by spaces do | ||
printf "%10s" " " | printf "%10s" " " | ||
Aktuelle Version vom 25. April 2013, 08:44 Uhr
string escaping
to 'bash'-escape a string use printf
a=''\''"\;:#[]{}()|&^$@!?, .<>abc123'
printf -v var "%q" "$a"
echo "$var"
\'\"\\\;:#\[\]\{\}\(\)\|\&\^\$@\!\?\,\ .\<\>abc123
have fun!
repeated output
if you want to format output e.g. by spaces do
printf "%10s" " "
this will produce a 10 bytes long string of ' ' (spaces).
if you want to have anything else than spaces use tr
printf "%10s" " " | tr ' ' '#' ##########
this is because non-given strings are interpretes as NULL-string
so the following does NOT work:
printf "%10s" "#"
#
printf expects a 10-byte long string because of the %10s format string.
because it only gets 1 byte. it prints out 9 bytes spaces and only ONE '#'
this is the reason you will have to use tr
