{"id":16971,"date":"2015-01-22T21:00:44","date_gmt":"2015-01-22T12:00:44","guid":{"rendered":"http:\/\/www.sssg.org\/blogs\/hiro345\/?p=16971"},"modified":"2015-02-24T06:42:47","modified_gmt":"2015-02-23T21:42:47","slug":"%e3%82%b3%e3%83%9e%e3%83%b3%e3%83%89%e3%81%ae%e5%ae%9f%e8%a1%8c%e7%b5%90%e6%9e%9c%e3%82%84%e3%82%a8%e3%83%a9%e3%83%bc%e3%83%a1%e3%83%83%e3%82%bb%e3%83%bc%e3%82%b8%e3%82%92%e7%a0%b4%e6%a3%84%e3%81%99","status":"publish","type":"post","link":"https:\/\/www.hiro345.net\/blogs\/hiro345\/archives\/16971.html","title":{"rendered":"\u30b3\u30de\u30f3\u30c9\u306e\u5b9f\u884c\u7d50\u679c\u3084\u30a8\u30e9\u30fc\u30e1\u30c3\u30bb\u30fc\u30b8\u3092\u7834\u68c4\u3059\u308b\u306b\u306f"},"content":{"rendered":"

\u6b21\u306e\u3088\u3046\u306a expr_sample0.sh \u304c\u3042\u3063\u305f\u3068\u3057\u307e\u3059\u3002<\/p>\n

\r\nexpr "$1" + 1 > \/dev\/null\r\nif [ $? -le 1 ]; then\r\n  echo "$1 is number"\r\nelse\r\n  echo "$1 is not number"\r\nfi\r\n<\/pre>\n
\u30b3\u30de\u30f3\u30c9\u3092\u5b9f\u884c\u3059\u308b\u3068\u304d\u306b\u30d1\u30e9\u30e1\u30fc\u30bf\u3078\u6570\u5b57\u3092\u6e21\u3059\u3068\u304d\u306f\u3044\u3044\u306e\u3067\u3059\u304c\u3001\u6587\u5b57\u3092\u6e21\u3057\u3066\u30a8\u30e9\u30fc\u3068\u3059\u308b\u3068\u304d\u306b\u3001expr\u30b3\u30de\u30f3\u30c9\u306e\u30a8\u30e9\u30fc\u3082\u4e00\u7dd2\u306b\u8868\u793a\u3055\u308c\u3066\u3057\u307e\u3044\u307e\u3059\u3002<\/p>\n
\r\n$ sh expr_sample0.sh 1\r\n1 is number\r\n$ sh expr_sample0.sh 2\r\n2 is number\r\n$ sh expr_sample0.sh a\r\nexpr: not a decimal number: 'a'\r\na is not number\r\n<\/pre>\n
\u30b3\u30de\u30f3\u30c9\u3092\u5b9f\u884c\u3057\u305f\u6642\u306b\u3001\u30b3\u30f3\u30bd\u30fc\u30eb\u753b\u9762\u3078\u30a8\u30e9\u30fc\u304c\u8868\u793a\u3055\u308c\u308b\u3068\u56f0\u308b\u3068\u304d\u3082\u3042\u308b\u306e\u3067\u3001\u30b9\u30af\u30ea\u30d7\u30c8\u3067\u4f7f\u3063\u3066\u3044\u308b\u30b3\u30de\u30f3\u30c9\u3067\u30a8\u30e9\u30fc\u304c\u767a\u751f\u3057\u305f\u5834\u5408\u306f\u4f55\u3082\u51fa\u529b\u3057\u306a\u3044\u3088\u3046\u306b\u3057\u305f\u3044\u3068\u304d\u304c\u3042\u308a\u307e\u3059\u3002
\n<\/p>\n
\u305d\u3093\u306a\u3068\u304d\u306f\u3001\u300c\u30b3\u30de\u30f3\u30c9 > \/dev\/null 2>& 1\u300d\u3068\u3057\u307e\u3059\u3002\u3053\u3053\u306e2\u306f\u30a8\u30e9\u30fc\u51fa\u529b\u7528\u306e\u30b9\u30da\u30b7\u30e3\u30eb\u30c7\u30d0\u30a4\u30b9\u30d5\u30a1\u30a4\u30eb\u3067\u30011\u306f\u6a19\u6e96\u51fa\u529b\u7528\u306e\u30b9\u30da\u30b7\u30e3\u30eb\u30c7\u30d0\u30a4\u30b9\u30d5\u30a1\u30a4\u30eb\u3092\u8868\u3057\u3066\u3044\u307e\u3059\u3002expr_sample0.sh \u3078\u9069\u7528\u3057\u3066\u307f\u307e\u3057\u3087\u3046\u3002<\/p>\n
\r\n$ cat expr_sample.sh \r\nexpr "$1" + 1 > \/dev\/null 2>& 1\r\nif [ $? -le 1 ]; then\r\n  echo "$1 is number"\r\nelse\r\n  echo "$1 is not number"\r\nfi\r\n<\/pre>\n
\u5b9f\u884c\u7d50\u679c\u306f\u6b21\u306e\u3088\u3046\u306b\u306a\u308a\u3001expr\u30b3\u30de\u30f3\u30c9\u306e\u5b9f\u884c\u7d50\u679c\u304c\u8868\u793a\u3055\u308c\u306a\u304f\u306a\u3063\u305f\u3053\u3068\u304c\u308f\u304b\u308a\u307e\u3059\u3002<\/p>\n
\r\n$  sh expr_sample.sh 2\r\n2 is number\r\n$ sh expr_sample.sh 3\r\n3 is number\r\n$ sh expr_sample.sh a\r\na is not number\r\n<\/pre>\n
\n