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-rw-r--r--node_modules/cross-spawn/lib/util/readShebang.js32
1 files changed, 32 insertions, 0 deletions
diff --git a/node_modules/cross-spawn/lib/util/readShebang.js b/node_modules/cross-spawn/lib/util/readShebang.js
new file mode 100644
index 0000000..bd4f128
--- /dev/null
+++ b/node_modules/cross-spawn/lib/util/readShebang.js
@@ -0,0 +1,32 @@
+'use strict';
+
+const fs = require('fs');
+const shebangCommand = require('shebang-command');
+
+function readShebang(command) {
+ // Read the first 150 bytes from the file
+ const size = 150;
+ let buffer;
+
+ if (Buffer.alloc) {
+ // Node.js v4.5+ / v5.10+
+ buffer = Buffer.alloc(size);
+ } else {
+ // Old Node.js API
+ buffer = new Buffer(size);
+ buffer.fill(0); // zero-fill
+ }
+
+ let fd;
+
+ try {
+ fd = fs.openSync(command, 'r');
+ fs.readSync(fd, buffer, 0, size, 0);
+ fs.closeSync(fd);
+ } catch (e) { /* Empty */ }
+
+ // Attempt to extract shebang (null is returned if not a shebang)
+ return shebangCommand(buffer.toString());
+}
+
+module.exports = readShebang;