The number of rows wc command to count the contents of the file, the number of words, the number of letters. But if you want to count the number of rows in a directory of all files, wc recursion does not provide statistics.
However, you can combine the find command, for example:
$ Wc -l `find -name * .c`
Wherein, -l parameter statistics the number of rows, find -name * .c is to find the current directory (including subdirectories) and all C files, `` is a shell replacement command.
Of course, there are many methods to achieve, I just think this is relatively simple and easy to remember.
Finally, with the use of what wc help (man wc)
wc - print newline, word, and byte counts for each file
wc [OPTION] ... [FILE] ...
wc [OPTION] ... --files0-from = F
Print newline, word, and byte counts for each FILE, and a total line if more than one FILE is specified With no FILE, or when FILE is -.., Read standard input A word is a non-zero-length sequence
of characters delimited by white space The options below may be used to select which counts are printed, always in the following order:. newline, word, character, byte, maximum line length.
print the byte counts
print the character counts
print the newline counts
--files0-from = F
read input from the files specified by NUL-terminated names in file F; If F is - then read names from standard input
print the length of the longest line
print the word counts
--help display this help and exit
output version information and exit