[unix-history] / usr / lib / learn / files / L5.1a

#print
Most UNIX commands, like "ls" and "cat", let you
specify any number of file names after the command.
To make this as easy as possible, there are some
ways to abbreviate file names.  This is usually
faster and more accurate than typing out the list in full.

For example, when the character "?" is used in a file name,
it will represent any character that might be
in a file name.  That is, the name "a?" is
an abbreviation for the files "a1", "a2", "aa",
and so forth.  You can say
  ls a?
and if there are any file names beginning with
"a" that are exactly two letters long, the computer
will tell you their names.  Try that here.
First list all the file names with "ls"; then type
  ls a?
to get all the two letter names beginning with "a".
Then type "ready".
#create a1
#create a12
#create abcdef
#create ax
#create aa
#copyin
#user
#uncopyin
grep '^ls a?$' .copy >/dev/null
#log
#next
5.1b 0
5.1c 5
5.1e 10
Commit	Line	Data
fed84c9b TL	1	#print
	2	Most UNIX commands, like "ls" and "cat", let you
	3	specify any number of file names after the command.
	4	To make this as easy as possible, there are some
	5	ways to abbreviate file names. This is usually
	6	faster and more accurate than typing out the list in full.
	7
	8	For example, when the character "?" is used in a file name,
	9	it will represent any character that might be
	10	in a file name. That is, the name "a?" is
	11	an abbreviation for the files "a1", "a2", "aa",
	12	and so forth. You can say
	13	ls a?
	14	and if there are any file names beginning with
	15	"a" that are exactly two letters long, the computer
	16	will tell you their names. Try that here.
	17	First list all the file names with "ls"; then type
	18	ls a?
	19	to get all the two letter names beginning with "a".
	20	Then type "ready".
	21	#create a1
	22	#create a12
	23	#create abcdef
	24	#create ax
	25	#create aa
	26	#copyin
	27	#user
	28	#uncopyin
	29	grep '^ls a?$' .copy >/dev/null
	30	#log
	31	#next
	32	5.1b 0
	33	5.1c 5
	34	5.1e 10