PHP float to int cast erratic behavior -

-

at least on machine:

$var = php_int_max; var_dump($var); $var++; var_dump((int)$var); $var += 10; var_dump((int)$var); $var += 10000; var_dump((int)$var);

results:

int(9223372036854775807)  int(-9223372036854775808)  int(-9223372036854775808)  int(-9223372036854765568)

why behavior crazy? understand returing php_min_int every time, if add numbers changes?

i these results when run code here:

http://writecodeonline.com/php/

it's undefined, float doesn't fit in integer. can happen. it's php, quirks. operation of casting implemented using (long) cast operation in c, undefined in case, shouldn't depend on particular behavior (in fact, on platforms, mips64, cause cpu exception, stop php).

source: http://www.php.net/manual/en/language.types.integer.php#language.types.integer.casting.from-float


Comments

Post a Comment

Popular posts from this blog

mysql - java.sql.SQLException Parameter index out of range (1 > number of parameters, which is 0) -

-
after validation of select combo box have selected not able insert in database. tomcat gives following error java.sql.sqlexception: parameter index out of range (1 > number of parameters, 0). how caused , how can solve it? you error when call of setxxx() methods on preparedstatement , while sql query string not have placeholders ? this. for example wrong : string sql = "insert tablename (col1, col2, col3) values (val1, val2, val3)"; // ... preparedstatement = connection.preparestatement(sql); preparedstatement.setstring(1, val1); // fail. preparedstatement.setstring(2, val2); preparedstatement.setstring(3, val3); you need fix sql query string accordingly specify placeholders. string sql = "insert tablename (col1, col2, col3) values (?, ?, ?)"; // ... preparedstatement = connection.preparestatement(sql); preparedstatement.setstring(1, val1); preparedstatement.setstring(2, val2); preparedstatement.setstring(3, val3); note parameter i...
Read more

c - ALSA programming: how to stop immediately -

-
i building audio app playback , stop features. function playaudio() playback, stopaudio() stop. expected file format wav. the main implementation of playaudio() below: playaudio() { ... ... int err = snd_pcm_open(&handle, "default", snd_pcm_stream_playback, 0); if ( err < 0 ) { printf("scm open failed: %s\n", snd_strerror(err)); exit(err); } while ( 0 < numofframes) { ... ... ssize_t frames = snd_pcm_writei(handle, &buffer[0], periodsize); ... ... } snd_pcm_drain(handle); snd_pcm_close(handle); } stopaudio() { snd_pcm_drop( m_handle ); } while audio playing back, program blocked @ line of snd_pcm_drain(handle); until playback completion. during period, expect stop audio play. action click stop button on ui , call snd_pcm_drop( m_handle ) finally. voice stopped, programm running still staying @ line of snd_pcm_drain(handle) untils several seconds later...
Read more