#29286 [NEW]: printf/sprintf floating point output change

From: michael at fishnet dot us Operating system: PHP version: 4.3.8 PHP Bug Type: Output Control Bug description: printf/sprintf floating point output change Description: ------------ The formatting of printf and sprint "%f" changed from 4.3.6 to 4.3.8. The change appears to have actually been released in 4.3.7, perhaps indicated by the Changelog line "Fixed problems with *printf() functions and '%f' formatting. (Marcus)". Where php has for years taken the format "%4.3f" as 4 places to the left of the decimal and 3 to the right of the decimal, it now reads it as "total width of 4 places, including the decimal point and 3 places to the right". Running the code sample provided between 4.3.6 and 4.3.8 will illustrate the problem. We use php to generate fixed width column files for an old database import system; we found to our surprise this morning that the nightly run did not work. The change broke significant operational code that has been in place for years. Warnings should have been blazened in red letters across the release that existing code could well break. Burying this in a cryptic one liner in the Changelog shows little forethought or consideration for those whose code suddenly will not work correctly, with no real warning at all. This probably will not be accepted as a bug. It seems to be an alignment of php with other language formatting systems, at least perl and C, and I understand that. I don't disagree with the philosophy of the change, but I strongly disagree with the way it was done. Though arguably with less impact, the number format change is comparable to the register_globals change. Putting the change into a security release worsened the impact, as one then has a choice to either stay with the security problems or find a fix unknown quantities of code. When a foundational behavior of php is being changed in the future, please document it profusely. Thank you. Reproduce code: --------------- <?php print "12345678901234567890123456789\n"; printf("%5.2f %8.2f\n",3.4,89); ?> Compare the output between 4.3.8 and 4.3.6. Expected result: ---------------- 4.3.6 output: 12345678901234567890123456789 3.40 89.00 Actual result: -------------- 4.3.8 output: 12345678901234567890123456789 3.40 89.00 -- Edit bug report at http://bugs.php.net/?id=29286&edit=1 -- Try a CVS snapshot (php4): http://bugs.php.net/fix.php?id=29286&r=trysnapshot4 Try a CVS snapshot (php5): http://bugs.php.net/fix.php?id=29286&r=trysnapshot5 Fixed in CVS: http://bugs.php.net/fix.php?id=29286&r=fixedcvs Fixed in release: http://bugs.php.net/fix.php?id=29286&r=alreadyfixed Need backtrace: http://bugs.php.net/fix.php?id=29286&r=needtrace Need Reproduce Script: http://bugs.php.net/fix.php?id=29286&r=needscript Try newer version: http://bugs.php.net/fix.php?id=29286&r=oldversion Not developer issue: http://bugs.php.net/fix.php?id=29286&r=support Expected behavior: http://bugs.php.net/fix.php?id=29286&r=notwrong Not enough info: http://bugs.php.net/fix.php?id=29286&r=notenoughinfo Submitted twice: http://bugs.php.net/fix.php?id=29286&r=submittedtwice register_globals: http://bugs.php.net/fix.php?id=29286&r=globals PHP 3 support discontinued: http://bugs.php.net/fix.php?id=29286&r=php3 Daylight Savings: http://bugs.php.net/fix.php?id=29286&r=dst IIS Stability: http://bugs.php.net/fix.php?id=29286&r=isapi Install GNU Sed: http://bugs.php.net/fix.php?id=29286&r=gnused Floating point limitations: http://bugs.php.net/fix.php?id=29286&r=float