我喜欢选定的答案。然而，它往往比awk慢，因为需要两个工具来完成这项工作。

$ wc -l file
49999998 file

$ time paste -sd+ file | bc
1448700364

real    1m36.960s
user    1m24.515s
sys     0m1.772s

$ time awk '{s+=$1}END{print s}' file
1448700364

real    0m45.476s
user    0m40.756s
sys     0m0.287s

如果你安装了ruby

cat FileWithColumnOfNumbers.txt | xargs ruby -e "puts ARGV.map(&:to_i).inject(&:+)"

[ghostdog74s评论的后续]

bash-2.03$ uname -sr
SunOS 5.8

bash-2.03$ perl -le 'print for 1..49999998' > infile

bash-2.03$ wc -l infile
 49999998 infile

bash-2.03$  time paste -sd+ infile | bc
bundling space exceeded on line 1, teletype
Broken Pipe

real    0m0.062s
user    0m0.010s
sys     0m0.010s

bash-2.03$ time nawk '{s+=$1}END{print s}' infile
1249999925000001

real    2m0.042s
user    1m59.220s
sys     0m0.590s
bash-2.03$ time /usr/xpg4/bin/awk '{s+=$1}END{print s}' infile
1249999925000001

real    2m27.260s
user    2m26.230s
sys     0m0.660s

bash-2.03$ time perl -nle'
  $s += $_; END { print $s }
   ' infile
1.249999925e+15

real    1m34.663s
user    1m33.710s
sys     0m0.650s

两行算吗?

awk '{ sum += $1; }
     END { print sum; }' "$@"

然后你就可以不用多余的'cat'了:

sum < FileWithColumnOfNumbers.txt
sum   FileWithColumnOfNumbers.txt

FWIW:在MacOS X上，你可以用一行程序完成:

awk '{ sum += $1; } END { print sum; }' "$@"

while read -r num; do ((sum += num)); done < inputfile; echo $sum

下面的命令将添加所有行(awk输出的第一个字段)

awk '{s+=$1} END {print s}' filename