diff options
Diffstat (limited to 'build-aux/useless-if-before-free')
| -rwxr-xr-x | build-aux/useless-if-before-free | 20 |
1 files changed, 17 insertions, 3 deletions
diff --git a/build-aux/useless-if-before-free b/build-aux/useless-if-before-free index 6d6b8d4199..0701e7b20b 100755 --- a/build-aux/useless-if-before-free +++ b/build-aux/useless-if-before-free @@ -1,6 +1,20 @@ -eval '(exit $?0)' && eval 'exec perl -wST "$0" "$@"' - & eval 'exec perl -wST "$0" $argv:q' - if 0; +#!/bin/sh +#! -*-perl-*- +# This is a prologue that allows to run a perl script as an executable +# on systems that are compliant to a POSIX version before POSIX:2017. +# On such systems, the usual invocation of an executable through execlp() +# or execvp() fails with ENOEXEC if it is a script that does not start +# with a #! line. The script interpreter mentioned in the #! line has +# to be /bin/sh, because on GuixSD systems that is the only program that +# has a fixed file name. The second line is for editing this file in +# Emacs. The next two lines below are valid code in both sh and perl. +# When executed by sh, they re-execute the script through the perl +# program found in $PATH. The '-x' option is essential; without it, +# perl would re-execute the script through /bin/sh. When executed by +# perl, the next two lines are a no-op. +eval 'exec perl -wSx "$0" "$@"' + if 0; + # Detect instances of "if (p) free (p);". # Likewise "if (p != 0)", "if (0 != p)", or with NULL; and with braces. |