On 28/11/15 23:34, Pádraig Brady wrote: > tag 22045 notabug > close 22045 > stop > > On 28/11/15 20:47, Matthias Klose wrote: >> found with coreutils-8.23, expr substr returns with an error code when the >> substring consists of only '0' characters, and the match is started at >> position 1. >> >> $ expr substr 00001234 3 4; echo $? >> 0012 >> 0 >> $ expr substr 1234 1 2; echo $? >> 12 >> 0 >> >> $ expr substr 00001234 1 2; echo $? >> 00 >> 1 >> $ expr substr 00001234 1 4; echo $? >> 0000 >> 1 >> $ expr substr 00001234 1 5; echo $? >> 00001 >> 0 > > This is a common gotcha. POSIX states that: > exit status of 1 is used if "the expression evaluates to null or zero". > > I must collate some gotchas like this.
Initial list started at: http://www.pixelbeat.org/docs/coreutils-gotchas.html
