TA貢獻1813條經(jīng)驗 獲得超2個贊
command -v <the_command>
bash
hash <the_command> # For regular commands. Or...type <the_command> # To check built-ins and keywords
whichhash, typecommand
which
甚至不設置退出狀態(tài)
if which foo
總
foo
hash
which
which
$ command -v foo >/dev/null 2>&1 || { echo >&2 "I require foo but it's not installed. Aborting."; exit 1; }$ type foo >/dev/null 2>&1 ||
{ echo >&2 "I require foo but it's not installed. Aborting."; exit 1; }$ hash foo 2>/dev/null ||
{ echo >&2 "I require foo but it's not installed. Aborting."; exit 1; }2>&-2>/dev/null2>&-
/bin/shtypehashhashtypecommand
bashtypehashtype-PPATHhash
gdatedate:
gnudate() {
if hash gdate 2>/dev/null; then
gdate "$@"
else
date "$@"
fi}
TA貢獻1817條經(jīng)驗 獲得超14個贊
$PATH 和
[ -x "$(command -v foo)" ]
if ! [ -x "$(command -v git)" ]; then echo 'Error: git is not installed.' >&2 exit 1fi
$PATH.
$PATH
舉報